Tutorial bug fix

[PhilippPlank]

Issue Number: #249

Objective of pull request: Tutorial07 should work again

Pull request checklist

Your PR fulfills the following requirements:

• Issue created that explains the change and why it's needed
• Tests are part of the PR (for bug fixes / features)
• Docs reviewed and added / updated if needed (for bug fixes / features)
• PR conforms to Coding Conventions
• PR applys BSD 3-clause or LGPL2.1+ Licenses to all code files
• Lint (flakeheaven lint src/lava tests/) and (bandit -r src/lava/.) pass locally
• Build tests (pytest) passes locally

Pull request type

Please check your PR type:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation changes
• Other (please describe):

What is the current behavior?

• No output, tutorial does not work

What is the new behavior?

• Outputs are generated as expected

Does this introduce a breaking change?

• Yes
• No

Supplemental information

[weidel-p]

This PR only changes two lines, setting the post_guard instead of the pre_guard and calling run_post_mgmt instead of run_pre_mgmt. That's fine for me.

[avitaleSon]

Is there a reason why the pre_guard and run_pre_mgmt dont work? Is this a bug or was it being called in the wrong way in Tutorial07?

[PhilippPlank]

They work, but to do what the tutorial is supposed to do, we would also need the lrn_guard to return true. The pre_mgmt phase is coupled with learning enabled.
I did not want to introduce this behavior in this tutorial, so I switched to the post_mgmt phase, which does not have this coupling.

[avitaleSon]

Thanks a lot for clarifying!