fix: text decorator on issue sidebar menu label (#27206) (#27209)

Backport #27206 by @metiftikci

fix underline for label on issue sidebar

Co-authored-by: metiftikci <metiftikci@hotmail.com>

templates/repo/issue/labels/label.tmpl

@@ -3,5 +3,5 @@
 	id="label_{{.label.ID}}"
 	href="{{.root.RepoLink}}/{{if or .root.IsPull .root.Issue.IsPull}}pulls{{else}}issues{{end}}?labels={{.label.ID}}"{{/* FIXME: use .root.Issue.Link or create .root.Link */}}
 >
-	{{RenderLabel $.Context .label}}
+	{{- RenderLabel $.Context .label -}}
 </a>