Ignore all launcher3 flaky test so that they come back online

Test dashboard: https://android-build.googleplex.com/builds/tests/search?filter=mediumFailureRate&filter=highFailureRate&query=config%3Av2%2Fgnl-eng%2Funbundled%2Flauncher%2Flauncher3_test_platform+latest%3A4d&tab=tests

Test: dashboard should not show flaky tests
Bug: 256832045
Change-Id: I06e879dec2703455b7be728c7afd3500d2edd54a