Update symfony/validator requirement from ^3.0 to ^4.4

[dependabot-preview]

Updates the requirements on symfony/validator to permit the latest version.

Changelog

Sourced from symfony/validator's changelog.

4.4.0

• added EnableAutoMapping and DisableAutoMapping constraints to enable or disable auto mapping for class or a property
• using anything else than a string as the code of a ConstraintViolation is deprecated, a string type-hint will
  be added to the constructor of the ConstraintViolation class and to the ConstraintViolationBuilder::setCode()
  method in 5.0
• deprecated passing an ExpressionLanguage instance as the second argument of ExpressionValidator::__construct(). Pass it as the first argument instead.
• added the compared_value_path parameter in violations when using any
  comparison constraint with the propertyPath option.
• added support for checking an array of types in TypeValidator
• added a new allowEmptyString option to the Length constraint to allow rejecting empty strings when min is set, by setting it to false.
• Added new minPropertyPath and maxPropertyPath options
  to Range constraint in order to get the value to compare
  from an array or object
• added the min_limit_path and max_limit_path parameters in violations when using
  Range constraint with respectively the minPropertyPath and
  maxPropertyPath options
• added a new notInRangeMessage option to the Range constraint that will
  be used in the violation builder when both min and max are not null
• added ability to use stringable objects as violation messages
• Overriding the methods ConstraintValidatorTestCase::setUp() and ConstraintValidatorTestCase::tearDown() without the void return-type is deprecated.
• deprecated Symfony\Component\Validator\Mapping\Cache\CacheInterface in favor of PSR-6.
• deprecated ValidatorBuilder::setMetadataCache, use ValidatorBuilder::setMappingCache instead.
• Marked the ValidatorDataCollector class as @final.

4.3.0

• added Timezone constraint
• added NotCompromisedPassword constraint
• added options iban and ibanPropertyPath to Bic constraint
• added UATP cards support to CardSchemeValidator
• added option allowNull to NotBlank constraint
• added Json constraint
• added Unique constraint
• added a new normalizer option to the string constraints and to the NotBlank constraint
• added Positive constraint
• added PositiveOrZero constraint
• added Negative constraint
• added NegativeOrZero constraint

4.2.0

• added a new UnexpectedValueException that can be thrown by constraint validators, these exceptions are caught by
  the validator and are converted into constraint violations
• added DivisibleBy constraint
• decoupled from symfony/translation by using Symfony\Contracts\Translation\TranslatorInterface
• deprecated ValidatorBuilderInterface

... (truncated)

Commits

• 56be252 Fix some \Throwable support remaining issues
• 3d7a182 Merge branch '4.3' into 4.4
• 8062841 Merge branch '3.4' into 4.3
• c8b4ae2 Unallow symfony/http-kernel ^5.0
• b11f457 minor #34135 [Validator] Add the missing translations for the Hebrew ("he") l...
• 8813200 [Validator] Add the missing translations for the Hebrew ("he") locale and f...
• 10d8029 Deprecate things that prevent \Throwable from bubbling down
• ad10075 Merge branch '4.3' into 4.4
• 0b52ec6 Merge branch '3.4' into 4.3
• d569fb2 minor #34160 Adding some validations tags on validators.et.xlf (glodzienski)
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
• @dependabot use these labels will set the current labels as the default for future PRs for this repo and language
• @dependabot use these reviewers will set the current reviewers as the default for future PRs for this repo and language
• @dependabot use these assignees will set the current assignees as the default for future PRs for this repo and language
• @dependabot use this milestone will set the current milestone as the default for future PRs for this repo and language
• @dependabot badge me will comment on this PR with code to add a "Dependabot enabled" badge to your readme

Additionally, you can set the following in your Dependabot dashboard:

• Update frequency (including time of day and day of week)
• Pull request limits (per update run and/or open at any time)
• Out-of-range updates (receive only lockfile updates, if desired)
• Security updates (receive only security updates, if desired)