Feature: alias close_modal action response to do_nothing

[G-Simpson]

Description

Added do_nothing alias for close_modal as described in issue #2944

Fixes #2944

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation added documentation for do_nothing alias docs.avohq.io#233
• I have added tests that prove my fix is effective or that my feature works

Manual review steps

1. head to http://localhost:3030/admin/resources/users/new
2. click "Actions"
3. click "Do nothing"
4. click "Run"

Manual reviewer: please leave a comment with output from the test if that's the case.

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[Paul-Bob]

It's looking good, thanks for looking into it @G-Simpson !

[adrianthedev]

Thanks for the contribution @G-Simpson!

[adrianthedev]

Thank you for your contribution @G-Simpson! This is a cool addition!