rewrite comments of Localizable.strings to better localize (#1355)

Co-authored-by: Kejia Kang <kekang@microsoft.com>

ios/FluentUI/Resources/Localization/en.lproj/Localizable.strings

@@ -7,10 +7,15 @@
 "Accessibility.ActivityIndicator.Animating.label" = "In progress";
 "Accessibility.ActivityIndicator.Stopped.label" = "Progress halted";
 
+/* Accessibility alert for common use */
 "Accessibility.Alert" = "Alert";
+/* Accessibility dismiss label for common use */
 "Accessibility.Dismiss.Label" = "Dismiss";
+/* Accessibility dismiss hint for common use */
 "Accessibility.Dismiss.Hint" = "Double tap to dismiss";
+/* Accessibility done label for common use */
 "Accessibility.Done.Label" = "Done";
+/* Accessibility multi select hint for common use */
 "Accessibility.MultiSelect.Hint" = "Double tap to toggle selection";
 
 /* Accessibility label for the upper calendar date picker view. */
@@ -150,7 +155,7 @@
 /* Day and time format string. Example: "Fri at 11:00 AM" */
 "Date.FormatDayTime" = "%@ at %@";
 
-// MSPersonaListView
+/* MSPersonaListView cell title: search(action) the directory */
 "MSPersonaListView.SearchDirectory" = "Search Directory";
 
 /* MSDateTimePicker label for the start time of a date range */