Unify main thread naming with mainline Robolectric

[mannodermaus]

I'm investigating the integration of the Roborazzi library with JUnit 5 via this extension and it works pretty well already. However, one thing I found is that it expects the main thread spun up by Robolectric to conform to a specific naming convention. You can see here that they expect the thread to have either Main Thread or Test worker in its name.

In the mainline Robolectric repository, the naming convention seems to be SDK xx Main Thread (link), but the JUnit 5 extension uses Main-Thread-<threadId>-SDK-xx instead (link). This causes the file name lookup function from Roborazzi to fail to detect the test method correctly.

FWIW, I have to submit some changes to Roborazzi anyway so that it can fully embrace JUnit 5, so I can also just extend their main thread checking logic while I'm at it. However, can we unify this name to match up with mainline Robolectric, or is there a reason for the difference (parallel test execution, maybe)? I can provide a pull request if necessary. Thanks!

[warnyul]

@mannodermaus I think we can change back the naming for SDK {apiLevel} Main Thread {threadId}

[warnyul]

Updated in 0.5.2