Add support for match expression

This is based on the work of [@g15ecb](https://github.com/g15ecb)

g15ecb@988efe9

Author: mdomke

syntax/python.vim

@@ -82,6 +82,7 @@ endif
 syn keyword pythonRepeat        for while
 syn keyword pythonConditional   if elif else
 syn keyword pythonException     try except finally
+syn keyword pythonMatch         match case
 " The standard pyrex.vim unconditionally removes the pythonInclude group, so
 " we provide a dummy group here to avoid crashing pyrex.vim.
 syn keyword pythonInclude       import
@@ -105,7 +106,7 @@ else
     syn match   pythonStatement   '\<async\s\+def\>' nextgroup=pythonFunction skipwhite
     syn match   pythonStatement   '\<async\s\+with\>'
     syn match   pythonStatement   '\<async\s\+for\>'
-    syn cluster pythonExpression contains=pythonStatement,pythonRepeat,pythonConditional,pythonOperator,pythonNumber,pythonHexNumber,pythonOctNumber,pythonBinNumber,pythonFloat,pythonString,pythonFString,pythonRawString,pythonRawFString,pythonBytes,pythonBoolean,pythonNone,pythonSingleton,pythonBuiltinObj,pythonBuiltinFunc,pythonBuiltinType,pythonClassVar
+    syn cluster pythonExpression contains=pythonStatement,pythonRepeat,pythonConditional,pythonMatch,pythonOperator,pythonNumber,pythonHexNumber,pythonOctNumber,pythonBinNumber,pythonFloat,pythonString,pythonFString,pythonRawString,pythonRawFString,pythonBytes,pythonBoolean,pythonNone,pythonSingleton,pythonBuiltinObj,pythonBuiltinFunc,pythonBuiltinType,pythonClassVar
 endif
 
 
@@ -434,6 +435,7 @@ if v:version >= 508 || !exists('did_python_syn_inits')
     HiLink pythonFunction         Function
     HiLink pythonFunctionCall     Function
     HiLink pythonConditional      Conditional
+    HiLink pythonMatch            Conditional
     HiLink pythonRepeat           Repeat
     HiLink pythonException        Exception
     HiLink pythonOperator         Operator