Add GitHub support for by ticket rule

[EmilMassey]

This PR (still a draft) adds GitHub support, but also tries to prepare an extension to support multiple issue trackers. I can see that there's already pending support for YouTrack #51, so I decided to publish this draft so we can discuss the direction together.

[staabm]

I like the direction

[staabm]

I think we need at least one real end-2-end test for github and jira

[EmilMassey]

I think we need at least one real end-2-end test for github and jira

Unfortunately I have no idea how to approach it. Do I understand correctly that we need to rely on real issues on GitHub / Jira?

1. Currently I see that current E2E tests workflow asserts only if no issues are reported. I think we should also be able to test if expected issues are present. How can we do it? I think about comparing it to a text file with expected errors (see 09f21fe), but I'm not sure if it's OK.
2. How to test if it works with open issues? Should we have an always-open dummy issue on GitHub?

GitHub API allows accessing public repositories without providing access token, but rate-limits apply (currently 60 requests per hour AFAIK). We'll probably need to use a secret in the CI with a token to avoid hitting the limits.

Do we need our own Jira board to be able to test it e2e? I know there are some public boards that we could access, but it's very risky to rely on some external board which may disappear some day.

[staabm]

I would be fine when the E2E test just triggers for a issue, no matter its state. I just want to see our curl client can connect, find the issue and get its state (for both trackers)

[staabm]

a few nits, but it looks really good already.

[staabm]

looks great. another one for jira please - after we merged the PR and verified this works in the pipeline as expected

[staabm]

I have fixed the github action, so the e2e tests should also work on forks now.
please rebase and we will see.

[staabm]

@EmilMassey would be great you could do the jira e2e test

[staabm]

I couldn't wait. love it

[staabm]

@EmilMassey why does the github tracker not need the resolved statuses?

don't we need the github ticket status in this list here to overcome the IF in

phpstan-todo-by/src/TodoByTicketRule.php

Lines 63 to 65 in 00690bb

	if (!in_array($ticketStatus, $this->configuration->getResolvedStatuses(), true)) {
	continue;
	}

?

[EmilMassey]

@staabm
In GitHub there are only two issue states: open and closed. This is different than Jira, where you can define your statuses according to your needs. So setting this parameter doesn't make sense for GitHub, because you always want to check if it is closed.

This condition you mentioned is satisfied because in TicketRuleConfigurationFactory we hardcode ['closed'] list as resolved statuses.