Fix dirty paint state in golden tests

[angelosilvestre]

Fix dirty paint stat in golden tests

The same issue that happened in #41 now is happening in super_editor in some Android golden tests:

══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following assertion was thrown running a test:
'package:flutter_test/src/_matchers_io.dart': Failed assertion: line 29 pos 10:
'!renderObject.debugNeedsPaint': is not true.

When the exception was thrown, this was the stack:
#2      captureImage (package:flutter_test/src/_matchers_io.dart:29:10)
#3      MatchesGoldenFile.matchAsync (package:flutter_test/src/_matchers_io.dart:96:21)
#4      _expect (package:matcher/src/expect/expect.dart:109:26)
#5      expectLater (package:matcher/src/expect/expect.dart:73:5)
#6      expectLater (package:flutter_test/src/widget_tester.dart:511:25)
#7      compareWithGolden (package:golden_toolkit/src/testing_tools.dart:296:9)

This is a test only issue.

To fix that, this PR changes the workaround added in #40 to run on all platforms.

[matthew-carroll]

LGTM - Remind me to cut a new release on our next call