PHPUnit 9 compatibility

[Naktibalda]

The following tests fail after upgrade to PHPUnit 9

1. FrameworksTest: See in field with boolean
   Test tests/unit/Codeception/Module/FrameworksTest.php:testSeeInFieldWithBoolean
   Failed asserting that `` is in input's value: array (
   0 => '',
   )
   Failed asserting that an array contains false.
   Support HTML5 form attribute #1 PHPUnit\Framework\Assert::assertContains
   Compatibility with Symfony 5 #2 /c/Projects/lib-innerbrowser/tests/unit/Codeception/Module/TestsForWeb.php:524

---

2. FrameworksTest: See in form fields
   Test tests/unit/Codeception/Module/FrameworksTest.php:testSeeInFormFields
   Failed asserting that `` is in input's value: array (
   0 => '',
   )
   Failed asserting that an array contains false.
   Support HTML5 form attribute #1 PHPUnit\Framework\Assert::assertContains
   Compatibility with Symfony 5 #2 /c/Projects/lib-innerbrowser/tests/unit/Codeception/Module/TestsForWeb.php:609

---

3. FrameworksTest: Checking options with complex names
   Test tests/unit/Codeception/Module/FrameworksTest.php:testCheckingOptionsWithComplexNames
   Failed asserting that an array contains 4.
   Support HTML5 form attribute #1 /c/Projects/lib-innerbrowser/tests/unit/Codeception/Module/TestsForWeb.php:1419

[Naktibalda]

in PHPUnit 9, assertContains uses === for comparison, so false does not match '' and 4 does not match '4'.

[Naktibalda]

Fixed by #8