Whitelist authorized_keys.lock in the gitlab:check rake task

changelogs/unreleased/38635-fix-gitlab-check-git-ssh-config.yml

+---
+title: Whitelist authorized_keys.lock in the gitlab:check rake task
+merge_request: 14624
+author:
+type: fixed

lib/system_check/app/git_user_default_ssh_config_check.rb

@@ -5,6 +5,7 @@ module SystemCheck
       # whitelisted as it may change the SSH client's behaviour dramatically.
       WHITELIST = %w[
         authorized_keys
+        authorized_keys.lock
         authorized_keys2
         known_hosts
       ].freeze

spec/lib/system_check/app/git_user_default_ssh_config_check_spec.rb

@@ -16,7 +16,12 @@ describe SystemCheck::App::GitUserDefaultSSHConfigCheck do
   end
 
   it 'only whitelists safe files' do
-    expect(described_class::WHITELIST).to contain_exactly('authorized_keys', 'authorized_keys2', 'known_hosts')
+    expect(described_class::WHITELIST).to contain_exactly(
+      'authorized_keys',
+      'authorized_keys2',
+      'authorized_keys.lock',
+      'known_hosts'
+    )
   end
 
   describe '#skip?' do