Improve tests' reliability (#763)

* Create publisher extension into the unit test target

* Add ViewModelContext test extension

* Refactor BugReportViewModelTests

* Fix failing UTs

* Idea PublishedClosure

* Refactor RoomDetailsViewModelTests

* Replace more Task.yield/Task.sleep

* Move leaveRoom/ignore/unignore under the @MainActor

* Revert "Idea PublishedClosure"

This reverts commit 4ab25291041f0dbd99083baf9d95bc6647f1fd97.

* Make process(viewAction:) sync

* Refactor BugReportViewModel callback to a publisher

* Fix UTs

* Refactor ReportContentViewModel

* Fix ui test build error

* Try make sonar happy

* Empty commit

* Revert "Try make sonar happy"

This reverts commit 97804b19373a8f55f12174ccbf27f1fd8db583b7.

* Rename ui test identifier

* Cleanup

* Callback -> actions refactor

* Update template

* Add publisher in TemplateCoordinator

* Add env variable in IntegrationTests.xctestplan

* Add async sequence extension

* Amend integration test plan

* Remove env variable from target.yml

* Cleanup

* Fix failing UI tests

UnitTests/SupportingFiles/target.yml

@@ -50,4 +50,3 @@ targets:
     - path: ../../Tools/Scripts/Templates/SimpleScreenExample/Tests/Unit
     - path: ../Resources
     - path: ../../ElementX/Sources/Other/InfoPlistReader.swift
-    - path: ../../ElementX/Sources/Other/Extensions/Publisher.swift