Don't show "Reference in new issue" when issues unit is globally disabled (#14437)

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

templates/repo/issue/view_content/context_menu.tmpl

@@ -12,7 +12,9 @@
 		{{ end }}
 		<div class="item context clipboard" data-clipboard-text="{{$referenceUrl}}">{{.ctx.i18n.Tr "repo.issues.context.copy_link"}}</div>
 		<div class="item context quote-reply {{if .diff}}quote-reply-diff{{end}}" data-target="{{.item.ID}}">{{.ctx.i18n.Tr "repo.issues.context.quote_reply"}}</div>
+		{{if not .ctx.UnitIssuesGlobalDisabled}}
 			<div class="item context reference-issue" data-target="{{.item.ID}}" data-modal="#reference-issue-modal" data-poster="{{.item.Poster.GetDisplayName}}" data-reference="{{$referenceUrl}}">{{.ctx.i18n.Tr "repo.issues.context.reference_issue"}}</div>
+		{{end}}
 		{{if or .ctx.Permission.IsAdmin .IsCommentPoster .ctx.HasIssuesOrPullsWritePermission}}
 			<div class="divider"></div>
 			<div class="item context edit-content">{{.ctx.i18n.Tr "repo.issues.context.edit"}}</div>