Reference labels by IDs instead of names in `keys` settings (#29194)

Here's the spec for the `for` attribute:
https://html.spec.whatwg.org/multipage/forms.html#attr-label-for

Signed-off-by: Yarden Shoham <git@yardenshoham.com>

templates/repo/settings/deploy_keys.tmpl

@@ -18,11 +18,11 @@
 						{{ctx.Locale.Tr "repo.settings.deploy_key_desc"}}
 					</div>
 					<div class="field {{if .Err_Title}}error{{end}}">
-						<label for="title">{{ctx.Locale.Tr "repo.settings.title"}}</label>
+						<label for="ssh-key-title">{{ctx.Locale.Tr "repo.settings.title"}}</label>
 						<input id="ssh-key-title" name="title" value="{{.title}}" autofocus required>
 					</div>
 					<div class="field {{if .Err_Content}}error{{end}}">
-						<label for="content">{{ctx.Locale.Tr "repo.settings.deploy_key_content"}}</label>
+						<label for="ssh-key-content">{{ctx.Locale.Tr "repo.settings.deploy_key_content"}}</label>
 						<textarea id="ssh-key-content" name="content" placeholder="{{ctx.Locale.Tr "settings.key_content_ssh_placeholder"}}" required>{{.content}}</textarea>
 					</div>
 					<div class="field">

templates/user/settings/keys_gpg.tmpl

@@ -10,7 +10,7 @@
 			{{.CsrfTokenHtml}}
 			<input type="hidden" name="title" value="none">
 			<div class="field {{if .Err_Content}}error{{end}}">
-				<label for="content">{{ctx.Locale.Tr "settings.key_content"}}</label>
+				<label for="gpg-key-content">{{ctx.Locale.Tr "settings.key_content"}}</label>
 				<textarea id="gpg-key-content" name="content" placeholder="{{ctx.Locale.Tr "settings.key_content_gpg_placeholder"}}" required>{{.content}}</textarea>
 			</div>
 			{{if .Err_Signature}}
@@ -26,7 +26,7 @@
 					</div>
 				</div>
 				<div class="field">
-					<label for="signature">{{ctx.Locale.Tr "settings.gpg_token_signature"}}</label>
+					<label for="gpg-key-signature">{{ctx.Locale.Tr "settings.gpg_token_signature"}}</label>
 					<textarea id="gpg-key-signature" name="signature" placeholder="{{ctx.Locale.Tr "settings.key_signature_gpg_placeholder"}}" required>{{.signature}}</textarea>
 				</div>
 			{{end}}

templates/user/settings/keys_principal.tmpl

@@ -44,7 +44,7 @@
 			<form class="ui form" action="{{.Link}}" method="post">
 				{{.CsrfTokenHtml}}
 				<div class="field {{if .Err_Content}}error{{end}}">
-					<label for="content">{{ctx.Locale.Tr "settings.principal_content"}}</label>
+					<label for="ssh-principal-content">{{ctx.Locale.Tr "settings.principal_content"}}</label>
 					<input id="ssh-principal-content" name="content" value="{{.content}}" autofocus required>
 				</div>
 				<input name="title" type="hidden" value="principal">

templates/user/settings/keys_ssh.tmpl

@@ -11,11 +11,11 @@
 		<form class="ui form" action="{{.Link}}" method="post">
 			{{.CsrfTokenHtml}}
 			<div class="field {{if .Err_Title}}error{{end}}">
-				<label for="title">{{ctx.Locale.Tr "settings.key_name"}}</label>
+				<label for="ssh-key-title">{{ctx.Locale.Tr "settings.key_name"}}</label>
 				<input id="ssh-key-title" name="title" value="{{.title}}" autofocus required maxlength="50">
 			</div>
 			<div class="field {{if .Err_Content}}error{{end}}">
-				<label for="content">{{ctx.Locale.Tr "settings.key_content"}}</label>
+				<label for="ssh-key-content">{{ctx.Locale.Tr "settings.key_content"}}</label>
 				<textarea id="ssh-key-content" name="content" class="js-quick-submit" placeholder="{{ctx.Locale.Tr "settings.key_content_ssh_placeholder"}}" required>{{.content}}</textarea>
 			</div>
 			<input name="type" type="hidden" value="ssh">