Bump doorkeeper from 5.5.0 to 5.5.1 (#16016)

Bumps [doorkeeper](https://github.com/doorkeeper-gem/doorkeeper) from 5.5.0 to 5.5.1.
- [Release notes](https://github.com/doorkeeper-gem/doorkeeper/releases)
- [Changelog](https://github.com/doorkeeper-gem/doorkeeper/blob/main/CHANGELOG.md)
- [Commits](https://github.com/doorkeeper-gem/doorkeeper/compare/v5.5.0...v5.5.1)

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

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

Gemfile.lock

@@ -203,7 +203,7 @@ GEM
     docile (1.3.4)
     domain_name (0.5.20190701)
       unf (>= 0.0.5, < 1.0.0)
-    doorkeeper (5.5.0)
+    doorkeeper (5.5.1)
       railties (>= 5)
     dotenv (2.7.6)
     dotenv-rails (2.7.6)
@@ -291,7 +291,7 @@ GEM
     httplog (1.4.3)
       rack (>= 1.0)
       rainbow (>= 2.0.0)
-    i18n (1.8.9)
+    i18n (1.8.10)
       concurrent-ruby (~> 1.0)
     i18n-tasks (0.9.34)
       activesupport (>= 4.0.2)
@@ -347,7 +347,7 @@ GEM
       activesupport (>= 4)
       railties (>= 4)
       request_store (~> 1.0)
-    loofah (2.9.0)
+    loofah (2.9.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)