chore(workflows): Use ubuntu-latest #1601

Job	Run time
test / test-dart-vm (3.0.1)	2m 12s
test / test-dart-vm (stable)	2m 31s
native_test / test-dart-native (macos-latest)	3m 8s
native_test / test-dart-native (windows-latest)	6m 13s
ddc_test / test-dart-ddc (3.0.1, chrome)	4m 23s
ddc_test / test-dart-ddc (3.0.1, firefox)	4m 47s
ddc_test / test-dart-ddc (stable, chrome)	3m 35s
ddc_test / test-dart-ddc (stable, firefox)	4m 40s
dart2js_test / test-dart-2js (3.0.1, chrome)	4m 40s
dart2js_test / test-dart-2js (3.0.1, firefox)	4m 26s
dart2js_test / test-dart-2js (stable, chrome)	4m 27s
dart2js_test / test-dart-2js (stable, firefox)	4m 39s
	49m 41s

Provide feedback