[HANDS-ON BUG] unit5 - /bin/bash: line 1: mlagents-learn: command not found

# Describe the bug

I can solve the one problem in this issue list.
```
# Go inside the repository and install the package
%cd ml-agents
!pip3 install -e ./ml-agents-envs
!pip3 install -e ./ml-agents
```
This part is so annoying, but I solved. Just type "%%capture" top of that codes.

But I have one more problem.

```
!mlagents-learn ./config/ppo/SnowballTarget.yaml --env=./training-envs-executables/linux/SnowballTarget/SnowballTarget --run-id="SnowballTarget1" --no-graphics
```
This part's output is `/bin/bash: line 1: mlagents-learn: command not found`.
I can't solve this bug. I tried `!pip install mlagents`, etc. But all failed.
please help me.

**Please share your notebook link so that we can reproduce the error**
https://colab.research.google.com/drive/1-O4EOsFTz3odNsDfib2EvU-jM6ACBbn3#scrollTo=bS-Yh1UdHfzy

# Material

- Did you use Google Colab? **Yes**

If not:
- Your Operating system (OS)
- Version of your OS