Fixed create branch button spinner after issue close

Fixes the create a branch button always being visible
after the issue is closed.

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/225303

app/assets/javascripts/issue.js

@@ -84,13 +84,7 @@ export default class Issue {
       projectIssuesCounter.text(addDelimiter(numProjectIssues));
 
       if (this.createMergeRequestDropdown) {
-        if (isClosed) {
-          this.createMergeRequestDropdown.unavailable();
-          this.createMergeRequestDropdown.disable();
-        } else {
-          // We should check in case a branch was created in another tab
-          this.createMergeRequestDropdown.checkAbilityToCreateBranch();
-        }
+        this.createMergeRequestDropdown.checkAbilityToCreateBranch();
       }
     } else {
       flash(issueFailMessage);

changelogs/unreleased/ph-225303-fixCreateBranchButtonSpinner.yml

+---
+title: Fixed create branch button not hiding when issue is closed
+merge_request: 47187
+author:
+type: fixed