pymoveit2 - Deadlock on waiting for gripper actions completion

**Current Situation:**
Trying to call `gripper_interface.wait_until_executed()` from the `pymoveit2` package in the `RobotDirector` object (`aegis_ros/aegis_director/aegis_director/robot_director.py`) causes a deadlock inside the `rclpy`'s waiting functions.

**Expected:**
Calling `gripper_interface.wait_until_executed()` should work as in the `pymoveit2`'s gripper examples.

**Workaround:**
Call dummy wait from the `time` library:
```python
import time
# ....
def _wait_for_gripper_execution(self) -> None:
time.sleep(0.1)
```