Fix protected branches API to accept name parameter with dot

changelogs/unreleased/42231-protected-branches-api-route-returns-404-for-branches-with-dots.yml

+---
+title: Fix protected branches API to accept name parameter with dot
+merge_request:
+author:
+type: fixed

lib/api/protected_branches.rb

@@ -2,7 +2,7 @@ module API
   class ProtectedBranches < Grape::API
     include PaginationParams
-    BRANCH_ENDPOINT_REQUIREMENTS = API::PROJECT_ENDPOINT_REQUIREMENTS.merge(branch: API::NO_SLASH_URL_PART_REGEX)
+    BRANCH_ENDPOINT_REQUIREMENTS = API::PROJECT_ENDPOINT_REQUIREMENTS.merge(name: API::NO_SLASH_URL_PART_REGEX)
     before { authorize_admin_project }

spec/requests/api/protected_branches_spec.rb

@@ -80,6 +80,12 @@ describe API::ProtectedBranches do
         it_behaves_like 'protected branch'
       end
+
+      context 'when protected branch contains a period' do
+        let(:protected_name) { 'my.feature' }
+
+        it_behaves_like 'protected branch'
+      end
     end
     context 'when authenticated as a guest' do