Compatibilize flicker tests with flicker infra refactor

Rename FlickerTestParameter(Factory) to FlickerTest(Factory)
Rename testSpec to flicker
Update factory method naming
Fix imports
Fix ktfmt formatting issues
Remove launcher strategy from helpers

Bug: 255715397
Test: atest FlickerTests WMShellFlickerTests
Change-Id: If0143ae3d94fd78a8339a69287072b3edbbbaca1