fix(HeaderLogo): 🐛 add alternative text

Signed-off-by: WaitSpring <me@waitspring.com>

resources/skins.citizen.styles/Header.less

@@ -60,6 +60,10 @@
 		padding: 0 var(--space-xs) 0 0;
 		border-right: 1px solid var(--border-color-base);
 		margin: 0 var(--space-xxs);
+
+		span {
+			text-indent: -9999px;
+		}
 	}
 
 	&__inner {

templates/Header__logo.mustache

@@ -18,6 +18,7 @@
 				}}{{/svg}}{{!
 			}}{{/icon}}"{{!
 			}} alt="{{msg-sitetitle}}" aria-hidden="true" height="32" width="32">
+		<span>{{msg-sitetitle}}</span>
 	</a>
 </div>
 {{/data-logos}}