Cover more classes and methods with BC promise

Author: ondrejmirtes

src/Type/Doctrine/ObjectMetadataResolver.php

@@ -36,6 +36,7 @@ public function __construct(
 		$this->repositoryClass = $repositoryClass;
 	}
 
+	/** @api */
 	public function getObjectManager(): ?ObjectManager
 	{
 		if ($this->objectManager === false) {

src/Type/Doctrine/Query/QueryType.php

@@ -6,6 +6,7 @@
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
 
+/** @api */
 class QueryType extends ObjectType
 {
 

src/Type/Doctrine/QueryBuilder/Expr/ExprType.php

@@ -4,6 +4,7 @@
 
 use PHPStan\Type\ObjectType;
 
+/** @api */
 class ExprType extends ObjectType
 {
 

src/Type/Doctrine/QueryBuilder/QueryBuilderType.php

@@ -6,6 +6,7 @@
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\Type;
 
+/** @api */
 abstract class QueryBuilderType extends ObjectType
 {