Update Validate to v1.20.0

[lognaturel]

Closes #799

Updates Validate to support the intersects function.

Why is this the best possible solution? Were any other approaches considered?

This updates Validate to add an intersects handler so that it can recognize the function when used for validation. It follows the pattern for new functions.

What are the regression risks?

It also updates JavaRosa so there's a chance an unrelated change could cause problems. The intersects change itself should be risk-free because it's additive.

Does this change require updates to documentation? If so, please file an issue here and include the link below.

getodk/xforms-spec#332, getodk/docs#2021

Before submitting this PR, please make sure you have:

• included test cases for core behavior and edge cases in tests
• run python -m unittest and verified all tests pass
• run ruff format pyxform tests and ruff check pyxform tests to lint code
• verified that any code or assets from external sources are properly credited in comments

[lognaturel]

https://github.com/getodk/javarosa/pull/781/changes which was released in Validate 1.20.0 re-established some checks for labels on internal choice lists that had accidentally been turned off in getodk/javarosa@847865c#diff-e045a71eed0a5d3fd849d1ca17f98246297bcae6d2d6b62203e17ec297365b03R348

It seems right to check them and in fact we have an issue for pyxform itself to do so (#534). I've quickly sanity checked that the Validate check still allows image-only options.