fix reference links

Author: StuartMosquera

docs/fsharp/language-reference/compiler-messages/fs0067.md

@@ -10,7 +10,7 @@ helpviewer_keywords:
 
 # FS0067: This type test or downcast will always hold
 
-This message is given when attempting to perform a type test ([:?](https://learn.microsoft.com/en-us/dotnet/fsharp/language-reference/match-expressions)) or downcast ([:?>](https://learn.microsoft.com/en-us/dotnet/fsharp/language-reference/casting-and-conversions#downcasting)) that will always succeed based on the types involved, making the operation unnecessary.
+This message is given when attempting to perform a type test ([:?](../match-expressions.md)) or downcast ([:?>](../casting-and-conversions.md#downcasting)) that will always succeed based on the types involved, making the operation unnecessary.
 
 Redundant Type test: