[lldb/tests] Removed add_test_categories decorator for python API tests, NFC

There is a .categories file in the python_api directory that makes all nested tests
belong to the category "pyapi". The decorator is unnecessary for these tests.

lldb/test/API/python_api/interpreter/TestCommandInterpreterAPI.py

@@ -20,7 +20,6 @@ class CommandInterpreterAPICase(TestBase):
         # Find the line number to break on inside main.cpp.
         self.line = line_number('main.c', 'Hello world.')
 
-    @add_test_categories(['pyapi'])
     def test_with_process_launch_api(self):
         """Test the SBCommandInterpreter APIs."""
         self.build()
@@ -74,7 +73,6 @@ class CommandInterpreterAPICase(TestBase):
         if self.TraceOn():
             lldbutil.print_stacktraces(process)
 
-    @add_test_categories(['pyapi'])
     def test_command_output(self):
         """Test command output handling."""
         ci = self.dbg.GetCommandInterpreter()