Fixes entry_point and kwargs in isaaclab_tasks README (isaac-sim#1485)

# Description

The entry_point `RLTaskEnv` doesn't exist

It should be `ManagerBasedRLEnv`

## Type of change

- This change requires a documentation update

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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Co-authored-by: Kelly Guo <[email protected]>

Author: fan-ziqi

source/extensions/omni.isaac.lab_tasks/docs/README.md

@@ -32,16 +32,26 @@ The environments are then registered in the `omni/isaac/lab_tasks/locomotion/vel
 ```python
 gym.register(
     id="Isaac-Velocity-Rough-Anymal-C-v0",
-    entry_point="omni.isaac.lab.envs:RLTaskEnv",
+    entry_point="omni.isaac.lab.envs:ManagerBasedRLEnv",
     disable_env_checker=True,
-    kwargs={"env_cfg_entry_point": f"{__name__}.rough_env_cfg:AnymalCRoughEnvCfg"},
+    kwargs={
+        "env_cfg_entry_point": f"{__name__}.rough_env_cfg:AnymalCRoughEnvCfg",
+        "rl_games_cfg_entry_point": f"{agents.__name__}:rl_games_rough_ppo_cfg.yaml",
+        "rsl_rl_cfg_entry_point": f"{agents.__name__}.rsl_rl_ppo_cfg:AnymalCRoughPPORunnerCfg",
+        "skrl_cfg_entry_point": f"{agents.__name__}:skrl_rough_ppo_cfg.yaml",
+    },
 )
 
 gym.register(
     id="Isaac-Velocity-Flat-Anymal-C-v0",
-    entry_point="omni.isaac.lab.envs:RLTaskEnv",
+    entry_point="omni.isaac.lab.envs:ManagerBasedRLEnv",
     disable_env_checker=True,
-    kwargs={"env_cfg_entry_point": f"{__name__}.flat_env_cfg:AnymalCFlatEnvCfg"},
+    kwargs={
+        "env_cfg_entry_point": f"{__name__}.flat_env_cfg:AnymalCFlatEnvCfg",
+        "rsl_rl_cfg_entry_point": f"{agents.__name__}.rsl_rl_ppo_cfg:AnymalCFlatPPORunnerCfg",
+        "rl_games_cfg_entry_point": f"{agents.__name__}:rl_games_flat_ppo_cfg.yaml",
+        "skrl_cfg_entry_point": f"{agents.__name__}:skrl_flat_ppo_cfg.yaml",
+    },
 )
 ```