Makes sure that data collection unit test works (#331)

# Description

This MR fixes the minor issues to ensure the data collection and
environment tests work.

## Type of change

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

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./orbit.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

source/extensions/omni.isaac.orbit_tasks/test/test_data_collector.py

@@ -5,6 +5,20 @@
 
 from __future__ import annotations
 
+"""Launch Isaac Sim Simulator first."""
+
+import os
+
+from omni.isaac.orbit.app import AppLauncher
+
+# launch the simulator
+app_experience = f"{os.environ['EXP_PATH']}/omni.isaac.sim.python.gym.headless.kit"
+app_launcher = AppLauncher(headless=True, experience=app_experience)
+simulation_app = app_launcher.app
+
+
+"""Rest everything follows."""
+
 import os
 import torch
 import unittest

source/extensions/omni.isaac.orbit_tasks/test/test_environments.py

@@ -51,7 +51,7 @@ class TestEnvironments(unittest.TestCase):
 
     def setUp(self) -> None:
         # common parameters
-        self.num_envs = 512
+        self.num_envs = 64
         self.use_gpu = True
 
     def test_random_actions(self):

source/extensions/omni.isaac.orbit_tasks/test/test_record_video.py

@@ -54,7 +54,7 @@ class TestRecordVideoWrapper(unittest.TestCase):
 
     def setUp(self) -> None:
         # common parameters
-        self.num_envs = 64
+        self.num_envs = 16
         self.use_gpu = True
         # video parameters
         self.step_trigger = lambda step: step % 225 == 0

source/extensions/omni.isaac.orbit_tasks/test/wrappers/test_rl_games_wrapper.py

@@ -54,7 +54,7 @@ class TestRlGamesVecEnvWrapper(unittest.TestCase):
 
     def setUp(self) -> None:
         # common parameters
-        self.num_envs = 512
+        self.num_envs = 64
         self.use_gpu = True
 
     def test_random_actions(self):

source/extensions/omni.isaac.orbit_tasks/test/wrappers/test_rsl_rl_wrapper.py

@@ -54,7 +54,7 @@ class TestRslRlVecEnvWrapper(unittest.TestCase):
 
     def setUp(self) -> None:
         # common parameters
-        self.num_envs = 512
+        self.num_envs = 64
         self.use_gpu = True
 
     def test_random_actions(self):

source/extensions/omni.isaac.orbit_tasks/test/wrappers/test_sb3_wrapper.py

@@ -55,7 +55,7 @@ class TestStableBaselines3VecEnvWrapper(unittest.TestCase):
 
     def setUp(self) -> None:
         # common parameters
-        self.num_envs = 512
+        self.num_envs = 64
         self.use_gpu = True
 
     def test_random_actions(self):