Fixed return values types to match the parent method types

tests/Platforms/OraclePlatformTest.php

@@ -87,7 +87,7 @@ class OraclePlatformTest extends AbstractPlatformTestCase
     }
 
     /**
-     * @return mixed[]
+     * {@inheritDoc}
      */
     public function getGenerateTableWithMultiColumnUniqueIndexSql() : array
     {
@@ -405,7 +405,7 @@ class OraclePlatformTest extends AbstractPlatformTestCase
     }
 
     /**
-     * @return mixed[]
+     * {@inheritDoc}
      */
     protected function getQuotedColumnInPrimaryKeySQL() : array
     {
@@ -413,7 +413,7 @@ class OraclePlatformTest extends AbstractPlatformTestCase
     }
 
     /**
-     * @return mixed[]
+     * {@inheritDoc}
      */
     protected function getQuotedColumnInIndexSQL() : array
     {
@@ -424,7 +424,7 @@ class OraclePlatformTest extends AbstractPlatformTestCase
     }
 
     /**
-     * @return mixed[]
+     * {@inheritDoc}
      */
     protected function getQuotedNameInIndexSQL() : array
     {
@@ -435,7 +435,7 @@ class OraclePlatformTest extends AbstractPlatformTestCase
     }
 
     /**
-     * @return mixed[]
+     * {@inheritDoc}
      */
     protected function getQuotedColumnInForeignKeySQL() : array
     {