fix typo (#42751)

Co-authored-by: Miguel Quiroz <[email protected]>

Author: magiudev

docs/fundamentals/implementations.md

@@ -17,7 +17,7 @@ Each implementation of .NET includes the following components:
 
 There are four .NET implementations that Microsoft supports:
 
-- .NET 6 and later versions
+- .NET 5 and later versions
 - .NET Framework
 - Mono
 - UWP