Bump flipper-ui from 1.3.6 to 1.4.0

Bumps [flipper-ui](https://github.com/flippercloud/flipper) from 1.3.6 to 1.4.0.
- [Release notes](https://github.com/flippercloud/flipper/releases)
- [Changelog](https://github.com/flippercloud/flipper/blob/main/Changelog.md)
- [Commits](https://github.com/flippercloud/flipper/compare/v1.3.6...v1.4.0)

---
updated-dependencies:
- dependency-name: flipper-ui
  dependency-version: 1.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Gemfile.lock

@@ -342,14 +342,14 @@ GEM
       websocket-driver (~> 0.7)
     ffaker (2.25.0)
     ffi (1.17.3)
-    flipper (1.3.6)
+    flipper (1.4.0)
       concurrent-ruby (< 2)
-    flipper-active_record (1.3.6)
+    flipper-active_record (1.4.0)
       activerecord (>= 4.2, < 9)
-      flipper (~> 1.3.6)
-    flipper-ui (1.3.6)
+      flipper (~> 1.4.0)
+    flipper-ui (1.4.0)
       erubi (>= 1.0.0, < 2.0.0)
-      flipper (~> 1.3.6)
+      flipper (~> 1.4.0)
       rack (>= 1.4, < 4)
       rack-protection (>= 1.5.3, < 5.0.0)
       rack-session (>= 1.0.2, < 3.0.0)