Restore support for ^8 || ^9

The minimum Drush version had to be lowered to to support older versions of Drupal.

Two tests failed for me with Drupal 9.5.11, PHP 8.1, and PHPUnit 9.6.23

There were 2 failures:

1) Drupal\Tests\duration_field\Unit\Normalizer\DurationIntervalNormalizerTest::testSupportsNormalization
Failed asserting that false is true.

/var/www/html/vendor/phpunit/phpunit/src/Framework/Constraint/Constraint.php:122
/var/www/html/vendor/phpunit/phpunit/src/Framework/Constraint/Constraint.php:56
/var/www/html/tests/src/Unit/Normalizer/DurationIntervalNormalizerTest.php:50
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestResult.php:729
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestSuite.php:685
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestSuite.php:685
/var/www/html/vendor/phpunit/phpunit/src/TextUI/TestRunner.php:651
/var/www/html/vendor/phpunit/phpunit/src/TextUI/Command.php:146
/var/www/html/vendor/phpunit/phpunit/src/TextUI/Command.php:99

2) Drupal\Tests\duration_field\Unit\Normalizer\DurationIntervalNormalizerTest::testSupportsDenormalization
Failed asserting that false is true.

/var/www/html/vendor/phpunit/phpunit/src/Framework/Constraint/Constraint.php:122
/var/www/html/vendor/phpunit/phpunit/src/Framework/Constraint/Constraint.php:56
/var/www/html/tests/src/Unit/Normalizer/DurationIntervalNormalizerTest.php:66
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestResult.php:729
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestSuite.php:685
/var/www/html/vendor/phpunit/phpunit/src/Framework/TestSuite.php:685
/var/www/html/vendor/phpunit/phpunit/src/TextUI/TestRunner.php:651
/var/www/html/vendor/phpunit/phpunit/src/TextUI/Command.php:146
/var/www/html/vendor/phpunit/phpunit/src/TextUI/Command.php:99

FAILURES!
Tests: 83, Assertions: 748, Failures: 2.

Duration field uses PHP 8.0 syntax.

Drupal 9.2 is the lowest version with stable php 8 support.

Automatically closed - issue fixed for 2 weeks with no activity.