fix: git push hook post receive (#38089)

* fix incorrect delayWriter call (there is already a defer call)
* split HookPostReceive into small functions
* fix incorrect HookPostReceiveResult response for errors
* fix incorrect AddRepoToLicenseUpdaterQueue call
* make sure repo home and branches page can work without default branch
* make sure default branch is always synchronized between database and
git repo, and fix FIXME

templates/repo/branch/list.tmpl

@@ -4,7 +4,6 @@
 	<div class="ui container">
 		{{template "base/alert" .}}
 		{{template "repo/sub_menu" .}}
-		{{if .DefaultBranchBranch}}
 			<h4 class="ui top attached header">
 				{{ctx.Locale.Tr "repo.default_branch"}}
 				{{if and $.IsWriter $.Repository.CanContentChange (not .IsDeleted)}}
@@ -14,7 +13,8 @@
 				{{end}}
 			</h4>
 
-			<div class="ui attached table segment">
+		{{if .DefaultBranchBranch}}
+			<div class="ui attached table segment" data-testid="branches-default-branch-list">
 				<table class="ui very basic fixed table single line">
 					<tbody>
 						<tr>
@@ -69,6 +69,10 @@
 					</tbody>
 				</table>
 			</div>
+		{{else}}
+			<div class="ui attached segment" data-testid="branches-default-branch-not-exist">
+				{{ctx.Locale.Tr "repo.branch.default_branch_not_exist" $.Repository.DefaultBranch}}
+			</div>
 		{{end}}
 
 		<h4 class="ui top attached header">