feat(scm): pull request file issues API

[cathteng]

API for users to upload their PR file information (filename, patch) to find issues associated with those files. This API can fetch issues for a single file.

This expands the scope of open PR issue comments beyond GitHub, and people can hit the API in their custom flows as well.

The API supports the ability to set a max limit on the number of issues to return, open PR comments only fetches a max of 5 per file -- using that as the default here.

[codecov[bot]]

:x: 12 Tests Failed:

Tests completed	Failed	Passed	Skipped
114	12	102	1

View the top 3 failed tests by shortest run time

 tests.sentry.api.endpoints.test_system_options

Stack Traces | 0s run time

No failure message available

 tests.sentry.hybridcloud.apigateway.test_apigateway

Stack Traces | 0s run time

No failure message available

 tests.sentry.middleware.integrations.parsers.test_github_enterprise

Stack Traces | 0s run time

No failure message available

To view individual test run time comparison to the main branch, go to the Test Analytics Dashboard

[getsantry[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[getsantry[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[getsantry[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀