Getting the following when using several of the assertContains based helpers methods.
[PHPUnit\Framework\Warning] Using assertContains() with string haystacks is deprecated and will not be supported in PHPUnit 9. Refactor your test to use assertStringContainsString() or assertStringContainsStringIgnoringCase() instead.
Was able to patch locally by updating:
assertContains => assertStringContainsString
assertNotContains => assertStringNotContainsString