typo: Double word "this" (dotnet/corefxdotnet/coreclr#36273)

Signed-off-by: Ndotnet-bot <dotnet-bot@microsoft.com>


Commit migrated from https://github.com/dotnet/coreclr/commit/df550d77db2e21ff19ac02f0421c26ca1c53231a

src/libraries/System.Private.CoreLib/src/System/Globalization/EastAsianLunisolarCalendar.cs

@@ -619,7 +619,7 @@ public override bool IsLeapMonth(int year, int month, int era)
 
         /// <summary>
         /// Returns  the leap month in a calendar year of the specified era. This method returns 0
-        /// if this this year is not a leap year.
+        /// if this year is not a leap year.
         /// </summary>
         public override int GetLeapMonth(int year, int era)
         {