Bug 1761266 - Add period to Focus promo subtitle string and tooltip text on Spotlight dismiss button r=flod,fluent-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D141968

browser/locales/en-US/browser/spotlight.ftl

@@ -4,6 +4,7 @@
 
 # Dialog close button
 spotlight-dialog-close-button =
+    .title = Close
     .aria-label = Close
 
 ## Mobile download button strings
@@ -16,6 +17,6 @@ spotlight-ios-marketplace-button =
 ## Firefox Focus promo message strings
 
 spotlight-focus-promo-title = Get { -focus-brand-name }
-spotlight-focus-promo-subtitle = Scan the QR code to download
+spotlight-focus-promo-subtitle = Scan the QR code to download.
 spotlight-focus-promo-qr-code =
     .alt = Scan the QR code to get { -focus-brand-name }