Update index.md

Author: ashitaprasad

contrib/advanced-python/index.md

@@ -12,7 +12,7 @@
 - [Protocols](protocols.md)
 - [Exception Handling in Python](exception-handling.md)
 - [Generators](generators.md)
-- [Match Case Statement](match_case_statement.md)
+- [Match Case Statement](match-case.md)
 - [Closures](closures.md)
 - [Filter](filter-function.md)
 - [Reduce](reduce-function.md)