Disables selection for rl_games when marl is selected for template generator (#567)

When user selects Multi-Agent for template generation, rl_games was one
of the rl_libraries options, but choosing it will generate no algorithm
template because we don't have any rl_game ma_ppo agent cfg. To reduce
the confusion, I will for now disable rl_games selection regarding
multi-agents, we can enable it again once we have a template for that.


## Type of change

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- Bug fix (non-breaking change which fixes an issue)


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tools/template/cli.py

@@ -218,15 +218,13 @@ def main() -> None:
         ", ".join(algorithms_per_rl_library.get("skrl", [])),
         ", ".join(algorithms_per_rl_library.get("sb3", [])),
     )
-    rl_library_table.add_row("Multi-agent support", State.Yes, State.No, State.Yes, State.No)
+    rl_library_table.add_row("Multi-agent support", State.No, State.No, State.Yes, State.No)
     rl_library_table.add_row("Distributed training", State.Yes, State.No, State.Yes, State.No)
     rl_library_table.add_row("Vectorized training", State.Yes, State.Yes, State.Yes, State.No)
     rl_library_table.add_row("Fundamental/composite spaces", State.No, State.No, State.Yes, State.No)
     cli_handler.output_table(rl_library_table)
     # - prompt for RL libraries
-    supported_rl_libraries = (
-        ["rl_games", "rsl_rl", "skrl", "sb3"] if len(single_agent_workflow) else ["rl_games", "skrl"]
-    )
+    supported_rl_libraries = ["rl_games", "rsl_rl", "skrl", "sb3"] if len(single_agent_workflow) else ["skrl"]
     selected_rl_libraries = cli_handler.get_choices(
         cli_handler.input_checkbox("RL library:", choices=[*supported_rl_libraries, "---", "all"]),
         default=supported_rl_libraries,