Add GitHub Actions workflow_call notification support

[sparksis]

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[sparksis]

@maintainers, apologies if this creates noise. I'll delete the PR if the tests fail locally by the end of the day 🙇

[sparksis]

Will revisit the future.

[caronc]

No need to close this, I'm sorry, i just hadn't had a chance to look further at it

[caronc]

Does this work for you if you do it manually; i don't see where this is documented very well. I found this gist which does a similar action but uses different headers and payloads.

[caronc]

Also, triggering a workflow doesn't really fit with the error/info/warning/success status states Apprise passes along with each call. Would these be simply ignored for this? I still see a use case for this... the schema is way to long though. Change it to somehting like githubwf:// or maybe just github:// ?

The url may need to be something like:

• schema://token@repository/workflow (as you have) ... but also:
• schema://token@repository/workflow1/workflow2/workflow3 ... support multiple workflows?