LNHU-265: Copy and style tweaks to v1 search widget form

[djanelle-mit]

Developer

Now that we've switched our homepage's search form copy, we want to mirror that on the v1 version. This work:

• Updates the label and placeholder strings to match SML and homepage
• Updates the search button to Red when enabled to match SML and homepage search buttons.

I noticed the v2 widget search button does not have a disabled state to match the v1's behavior, and added that to a future ticket.

https://mitlibraries.atlassian.net/browse/LHNU-265

Stylesheets

• Any theme or plugin whose stylesheets have changed has had its version
  string incremented.

Secrets

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• Relevant secrets have been updated in Github Actions
• All new secrets documented in README

Documentation

• Project documentation has been updated
• No documentation changes are needed

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• ANDI or Wave has been run in accordance to
  our guide and
  all issues introduced by these changes have been resolved or opened as new
  issues (link to those issues in the Pull Request details above)

Stakeholder approval

• Stakeholder approval has been confirmed
• Stakeholder approval is not needed

Dependencies

YES | NO dependencies are updated

Code Reviewer

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  (not just this pull request message)
• The changes have been verified
• The documentation has been updated or is unnecessary
• New dependencies are appropriate or there were no changes

[matt-bernhardt]

This looks fine to me, so

(My assumption about this is that the CSS stylesheet for this plugin is still in v1 mode, which is why we're not relying on the color variables that were defined for the new homepage?)

[djanelle-mit]

(My assumption about this is that the CSS stylesheet for this plugin is still in v1 mode, which is why we're not relying on the color variables that were defined for the new homepage?)

Yep, exactly. One of the many tendrils we'd need to investigate as we migrate from v1 to v2.