Add protected branch name description (#27257) (#27351)

Backport #27257 by @lunny

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: delvh <dev.lh@web.de>

options/locale/locale_en-US.ini

@@ -2305,6 +2305,7 @@ settings.dismiss_stale_approvals_desc = When new commits that change the content
 settings.require_signed_commits = Require Signed Commits
 settings.require_signed_commits_desc = Reject pushes to this branch if they are unsigned or unverifiable.
 settings.protect_branch_name_pattern = Protected Branch Name Pattern
+settings.protect_branch_name_pattern_desc = "Protected branch name patterns. See <a href="github.com/gobwas/glob">the documentation</a> for pattern syntax. Examples: main, release/**"
 settings.protect_patterns = Patterns
 settings.protect_protected_file_patterns = "Protected file patterns (separated using semicolon ';'):"
 settings.protect_protected_file_patterns_desc = "Protected files are not allowed to be changed directly even if user has rights to add, edit, or delete files in this branch. Multiple patterns can be separated using semicolon (';'). See <a href='https://pkg.go.dev/github.com/gobwas/glob#Compile'>github.com/gobwas/glob</a> documentation for pattern syntax. Examples: <code>.drone.yml</code>, <code>/docs/**/*.txt</code>."

templates/repo/settings/protected_branch.tmpl

@@ -10,6 +10,7 @@
 					<label>{{ctx.Locale.Tr "repo.settings.protect_branch_name_pattern"}}</label>
 					<input name="rule_name" type="text" value="{{.Rule.RuleName}}">
 					<input name="rule_id" type="hidden" value="{{.Rule.ID}}">
+					<p class="help gt-ml-0">{{ctx.Locale.Tr "repo.settings.protect_branch_name_pattern_desc" | Safe}}</p>
 				</div>
 				<div class="field">
 					<label>{{ctx.Locale.Tr "repo.settings.protect_protected_file_patterns"}}</label>