Fix CI pipeline

[kstenerud]

Goal

Temporarily work around BB issues to get CI pipeline running again.

[github-actions]

Bugsnag.framework binary size did not change - 713,104 bytes

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[twometresteve]

Changes so far look fine, but:

1. I think there are more app hang scenarios that need skipping. "Fatal app hangs should be reported if the app hangs before going to the background" seemed to kill the appium session. I would probably just skip the whole of that feature file.
2. There are also iOS 11 steps in pipeline.full.yml that need skipping - otherwise the overnight run will just keep failing.

[twometresteve]

Could you also include the trivial changes from https://github.com/bugsnag/bugsnag-cocoa/pull/1595/files to save another loop around the build houses?