Bump trix from 2.1.5 to 2.1.7 (#3591)

Bumps [trix](https://github.com/basecamp/trix) from 2.1.5 to 2.1.7.
- [Release notes](https://github.com/basecamp/trix/releases)
- [Commits](basecamp/trix@v2.1.5...v2.1.7)

---
updated-dependencies:
- dependency-name: trix
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -22,7 +22,7 @@
     "popper.js": "^1.16.0",
     "sass": "^1.77.8",
     "selectize": "^0.12.6",
-    "trix": "^2.1.5",
+    "trix": "^2.1.7",
     "turbolinks": "^5.2.0"
   },
   "devDependencies": {