Bump mobility from 1.2.9 to 1.3.1

Bumps [mobility](https://github.com/shioyama/mobility) from 1.2.9 to 1.3.1.
- [Release notes](https://github.com/shioyama/mobility/releases)
- [Changelog](https://github.com/shioyama/mobility/blob/master/CHANGELOG.md)
- [Commits](shioyama/mobility@v1.2.9...v1.3.1)

---
updated-dependencies:
- dependency-name: mobility
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile.lock

@@ -387,7 +387,7 @@ GEM
     mini_magick (4.13.2)
     mini_mime (1.1.5)
     minitest (5.25.2)
-    mobility (1.2.9)
+    mobility (1.3.1)
       i18n (>= 0.6.10, < 2)
       request_store (~> 1.0)
     mobility-actiontext (1.1.1)