Merge branch '7.0' into 7.1

* 7.0:
  Fix merge
  Sync .github/expected-missing-return-types.diff

Author: nicolas-grekas

Tests/DependencyInjection/ConfigurationTest.php

@@ -573,6 +573,7 @@ public function testSerializerJsonDetailedErrorMessagesEnabledWhenDefaultContext
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(true), [
             [
+                'http_method_override' => false,
                 'serializer' => [
                     'default_context' => [
                         'foo' => 'bar',
@@ -589,6 +590,7 @@ public function testSerializerJsonDetailedErrorMessagesInDefaultContextCanBeDisa
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(true), [
             [
+                'http_method_override' => false,
                 'serializer' => [
                     'default_context' => [
                         'foo' => 'bar',
@@ -606,6 +608,7 @@ public function testSerializerJsonDetailedErrorMessagesInDefaultContextCanBeDisa
         $processor = new Processor();
         $config = $processor->processConfiguration(new Configuration(true), [
             [
+                'http_method_override' => false,
                 'serializer' => [
                     'default_context' => [
                         'foo' => 'bar',