fix intersection types in tests

Author: Tobion

Tests/CacheWarmer/AnnotationsCacheWarmerTest.php

@@ -169,7 +169,7 @@ public function testWarmupRemoveCacheMisses()
     /**
      * @return MockObject&Reader
      */
-    private function getReadOnlyReader()
+    private function getReadOnlyReader(): Reader
     {
         $readerMock = $this->createMock(Reader::class);
         $readerMock->expects($this->exactly(0))->method('getClassAnnotations');

Tests/Command/CachePoolDeleteCommandTest.php

@@ -86,7 +86,7 @@ public function testCommandDeleteFailed()
     /**
      * @return MockObject&KernelInterface
      */
-    private function getKernel()
+    private function getKernel(): KernelInterface
     {
         $container = $this->createMock(ContainerInterface::class);
 

Tests/Command/CachePruneCommandTest.php

@@ -53,7 +53,7 @@ private function getEmptyRewindableGenerator(): RewindableGenerator
     /**
      * @return MockObject&KernelInterface
      */
-    private function getKernel()
+    private function getKernel(): KernelInterface
     {
         $container = $this->createMock(ContainerInterface::class);
 
@@ -74,7 +74,7 @@ private function getKernel()
     /**
      * @return MockObject&PruneableInterface
      */
-    private function getPruneableInterfaceMock()
+    private function getPruneableInterfaceMock(): PruneableInterface
     {
         $pruneable = $this->createMock(PruneableInterface::class);
         $pruneable