Added the "timeout_wait" parameter to the CLI ("--timeout-wait=").

[max-krichenbauer]

Proposed change(s)

The timeout_wait parameter was not accessible through the CLI.
This is a problem when people need to debug their Unity scripts (temporarily pausing execution in the Unity Editor),
or when training is performed with human-in-the-loop,
as ml-agents will terminate the session after mere 60 seconds and throw a "UnityTimeOutException: The Unity environment took too long to respond."

Users should be able to set the timeout through the CLI with
--timeout-wait=<seconds>

Useful links (Github issues, JIRA tickets, ML-Agents forum threads etc.)

Types of change(s)

• Bug fix
• New feature
• Code refactor
• Breaking change
• Documentation update
• Other (please describe)

Checklist

• Added tests that prove my fix is effective or that my feature works
• Updated the changelog (if applicable)
• Updated the documentation (if applicable)
• Updated the migration guide (if applicable)

Other comments

[CLAassistant]

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