Dashboard: Fix typos in feedback request sentence (#54429)

* Fix typo in feedback request

* prettier

Co-authored-by: Domas <domasx2@gmail.com>

public/app/features/dashboard/components/ShareModal/SharePublicDashboard.tsx

@@ -116,8 +116,9 @@ export const SharePublicDashboard = (props: Props) => {
             rel="noreferrer"
             className="text-link"
           >
-            github discussion
+            GitHub discussion
           </a>
+          .
           <hr />
           <div>
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