Fix EnforcementActionsFilterForm

[Scotchester]

This started throwing a 500 with the addition of #6080. It needed its custom get_query_strings method to get the same is_archived addition as the general FilterableListForm.

I'm not sure why this doesn't also need to be done for the EventArchiveFilterForm just below this one.

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Additions

Removals

Changes

How to test this PR

Screenshots

Notes and todos

Checklist

• PR has an informative and human-readable title
  • PR titles are used to generate the change log in releases; good ones make that easier to scan.
  • Consider prefixing, e.g., "Mega Menu: fix layout bug", or "Docs: Update Docker installation instructions".
• Changes are limited to a single goal (no scope creep)
• Code follows the standards laid out in the CFPB development guidelines
• Future todos are captured in comments and/or tickets
• Project documentation has been updated, potentially one or more of:
  • This repo’s docs (edit the files in the /docs folder) – for basic, close-to-the-code docs on working with this repo
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  • CFPB/hubcap wiki on GHE – for internal CFPB design and content guidance

Front-end testing

Browser testing

Visually tested in the following supported browsers:

• Firefox
• Chrome
• Safari
• Edge 18 (the last Edge prior to it switching to Chromium)
• Internet Explorer 11 and 8 (via emulation in 11's dev tools)
• Safari on iOS
• Chrome on Android

Accessibility

• Keyboard friendly (navigable with tab, space, enter, arrow keys, etc.)
• Screen reader friendly
• Does not introduce new errors or warnings in WAVE

Other

• Is useable without CSS
• Is useable without JS
• Does not introduce new lint warnings
• Flexible from small to large screens