feat: create parity issue workflow

[joshgummersall]

This workflow will create a parity issue that includes a short summary
and a link to a pull request, along with the parity label, to keep us
honest!

It will trigger on manual dispatch - actions will need to be added to
other repos to trigger this workflow.

[joshgummersall]

The relevant dotnet PR is here: microsoft/botbuilder-dotnet#4997

[joshgummersall]

Here is a sample issue from testing against some of my personal repos: https://github.com/joshgummersall/ts-plugin-mvp/issues/29

[stevengum]

This is a good start, in the future we might have to write a custom workflow to get to where we want (i.e. if some change occurs in the *.sln or *.csproj files in .NET we likely don't need those changes in JS or Python)

Also, it seems like it might be possible to get the PRs linked issue according to this this doc page.

(Reached via https://docs.github.com/en/free-pro-team@latest/developers/webhooks-and-events/webhook-events-and-payloads#pull_request)

[stevengum]

@EricDahlvang FYI, @luhan2017, @chon219, @johnataylor, @gabog

[coveralls]

Pull Request Test Coverage Report for Build 375315638

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.007%) to 84.778%

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Totals
Change from base Build 371483751:	-0.007%
Covered Lines:	17312
Relevant Lines:	19498

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💛 - Coveralls

[joshgummersall]

Any repo that is "downstream" of botbuilder-dotnet can copy our template here and augment the workflow file to trigger.

[joshgummersall]

@stevengum my goal was to use the simplest primitives possible in the bb-js repo and rely on upstream producers to determine when to trigger this action. Specifically, we could adjust the PR merge workflow in the botbuilder-dotnet to filter certain files via globs, or the like. This is basically an API endpoint for other things to use when they think we ought to have a new parity issue opened. I could possibly even adjust it to accept a title, description, and ref instead of being pull request specific to support issues as well.

[joshgummersall]

@gabog this action might be useful in writing a workflow to automatically create child issues from a parent botframework-sdk issue.