Marked Consumer Process Funcs as Override (#1370)

Should make sure that generation of derived class functions declarations can never drift from base
class versions leading to base class stubs being silently called.
Note we should drop the virtual since it is redundant but doing that is another story and will be
told another day. Handy dandy style guideline about it:
https://bit.ly/3R0UAo4

Author: andrew-lunarg

framework/generated/dx12_generators/dx12_replay_consumer_header_generator.py

@@ -60,4 +60,4 @@ def write_include(self):
         write(code, file=self.outFile)
 
     def get_consumer_function_body(self, class_name, method_info, return_type):
-        return ';'
+        return ' override;'