do not remove the viewbox from svgs

[gthayer]

Description of the Change

Opened an issue here: #130

Benefits

SVGs will display correctly on deployment

Possible Drawbacks

Perhaps there is a reason viewbox is removed which I am unaware of.

Verification Process

1. If you site has SVGs, run npm run build to see the cropping
2. npm run watch does not include the cropping because ImageminPlugin is disabled on non-production environments,.

Checklist:

• [x ] I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests passed.

Changelog Entry

Allowed for the display of SVG viewbox attributes when built in a production environment.

[joesnellpdx]

@gthayer

This looks fine to me. FYI - we will be moving to a singular scaffold soon - WIP: https://github.com/10up/wp-scaffold