Add CI job that runs the full load test suite

[allenlsy]

Please describe what should be documented

This is a sub-issue for #4822

Create a CI job runs the internal OSM load test suite (currently a private project) periodically.

This CI job works as:

1. Pull osm-perftest repo.
2. Execute the script that performs the full load test suite. The final result will be saved in a local csv file on the job VM.
3. Output the results to a certain page. Possible solutions are: a Github wiki page, as comment to the latest merged PR, or cloud file storage.

In order to implement step 1, an access token should be created in osm-perftest and secret should be added to osm repo.

Please suggest where in the repo the document should be located

[steeling]

do you know what scopes you need the token to have? https://docs.github.com/en/developers/apps/building-oauth-apps/scopes-for-oauth-apps#available-scopes

[allenlsy]

@steeling since the job only need to read osm-perftest repo, according to the doc, I think (no scope) grants read-only permission which is sufficient for our case.

If not, maybe read:repo_hook is what we are looking for.

[steeling]

A PAT will give access to a user's private repo's, so we should figure out another way to do this, including considering open sourcing that repo if we want.

[github-actions[bot]]

Added default label kind/needed. Please consider re-labeling this issue appropriately.