Fix ref links in issue overviews for tags (#8742)

* Properly generate ref URLs

Tags used to not generate correct URLs (src/branch/tags/1.0.0 instead of
src/tags/1.0.0).

Also cleans up some code around it with the created helper functions.

* Fix formatting and create migration

* Add copyright head to utils_test

* Use a raw query for the ref migration

* Remove semicolon

* Quote column and table names in migration SQL

* Change || to CONCAT, since MSSQL does not support ||

* Make migration engine aware

* Add missing import

* Move ref EndName and URL to the issue service

* Fix tests

* Add test for commit refs

* Update issue.go

* Use the right command for building JavaScript bundles

* Prepare for merge

* Check for refs/* before prepending in migration

* Update services/issue/issue_test.go

* Update modules/git/utils_test.go

Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: techknowlogick <matti@mdranta.net>

routers/repo/issue.go

@@ -286,6 +286,9 @@ func issues(ctx *context.Context, milestoneID int64, isPullOption util.OptionalB
 		assigneeID = 0 // Reset ID to prevent unexpected selection of assignee.
 	}
 
+	ctx.Data["IssueRefEndNames"], ctx.Data["IssueRefURLs"] =
+		issue_service.GetRefEndNamesAndURLs(issues, ctx.Repo.RepoLink)
+
 	ctx.Data["ApprovalCounts"] = func(issueID int64, typ string) int64 {
 		counts, ok := approvalCounts[issueID]
 		if !ok || len(counts) == 0 {
@@ -1127,6 +1130,7 @@ func ViewIssue(ctx *context.Context) {
 	ctx.Data["HasIssuesOrPullsWritePermission"] = ctx.Repo.CanWriteIssuesOrPulls(issue.IsPull)
 	ctx.Data["IsRepoAdmin"] = ctx.IsSigned && (ctx.Repo.IsAdmin() || ctx.User.IsAdmin)
 	ctx.Data["LockReasons"] = setting.Repository.Issue.LockReasons
+	ctx.Data["RefEndName"] = git.RefEndName(issue.Ref)
 	ctx.HTML(200, tplIssueView)
 }