Fix phpcs coding standard violations

Remove unused InvalidArgumentException import from RecordingAdapter,
extract assignment out of if condition in PostgresAdapter, and remove
blank line before closing brace in ForeignKeyTest.

Author: jamisonbryant

src/Db/Adapter/PostgresAdapter.php

@@ -505,7 +505,8 @@ protected function getChangeColumnInstructions(
                 'ALTER COLUMN %s',
                 $quotedColumnName,
             );
-            if ($newColumn->isIdentity() && ($generated = $newColumn->getGenerated()) !== null) {
+            $generated = $newColumn->getGenerated();
+            if ($newColumn->isIdentity() && $generated !== null) {
                 if ($column->isIdentity()) {
                     $sql .= sprintf(' SET GENERATED %s', $generated);
                 } else {

src/Db/Adapter/RecordingAdapter.php

@@ -12,7 +12,6 @@
 use Migrations\Db\Action\AddForeignKey;
 use Migrations\Db\Action\AddIndex;
 use Migrations\Db\Action\CreateTable;
-use InvalidArgumentException;
 use Migrations\Db\Action\DropForeignKey;
 use Migrations\Db\Action\DropIndex;
 use Migrations\Db\Action\DropTable;

tests/TestCase/Db/Table/ForeignKeyTest.php

@@ -151,5 +151,4 @@ public function testThrowsErrorForInvalidDeferrableValue(): void
         $this->expectException(InvalidArgumentException::class);
         $this->fk->setDeferrableMode('invalid_value');
     }
-
 }