minor #50821 Add missing return types and enforce return types on all methods (wouterj)

This PR was squashed before being merged into the 6.4 branch.

Discussion
----------

Add missing return types and enforce return types on all methods

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | yes
| Tickets       | -
| License       | MIT
| Doc PR        | -

In 6.3, we enforced return types on all interface methods. We're missing just a handful return types on non-interface methods (all fixed in this PR). As you can see, the added return types are either data collectors or methods introduced by 6.3 features.

In my opinion, we should start to enforce return types on all methods from 6.4 (either as PHPdoc - for `resource` and to avoid BC breaks - or PHP native declaration).

Commits
-------

189c3c8fa1 Add missing return types and enforce return types on all methods

Author: nicolas-grekas

DataCollector/DoctrineDataCollector.php

@@ -113,11 +113,17 @@ public function reset()
         }
     }
 
+    /**
+     * @return array
+     */
     public function getManagers()
     {
         return $this->data['managers'];
     }
 
+    /**
+     * @return array
+     */
     public function getConnections()
     {
         return $this->data['connections'];
@@ -131,11 +137,17 @@ public function getQueryCount()
         return array_sum(array_map('count', $this->data['queries']));
     }
 
+    /**
+     * @return array
+     */
     public function getQueries()
     {
         return $this->data['queries'];
     }
 
+    /**
+     * @return int
+     */
     public function getTime()
     {
         $time = 0;

DependencyInjection/CompilerPass/RegisterEventListenersAndSubscribersPass.php

@@ -53,6 +53,9 @@ public function __construct(string $connectionsParameter, string $managerTemplat
         $this->tagPrefix = $tagPrefix;
     }
 
+    /**
+     * @return void
+     */
     public function process(ContainerBuilder $container)
     {
         if (!$container->hasParameter($this->connectionsParameter)) {

Form/DoctrineOrmTypeGuesser.php

@@ -12,6 +12,7 @@
 namespace Symfony\Bridge\Doctrine\Form;
 
 use Doctrine\DBAL\Types\Types;
+use Doctrine\ORM\Mapping\ClassMetadata;
 use Doctrine\ORM\Mapping\ClassMetadataInfo;
 use Doctrine\ORM\Mapping\MappingException as LegacyMappingException;
 use Doctrine\Persistence\ManagerRegistry;
@@ -151,6 +152,13 @@ public function guessPattern(string $class, string $property): ?ValueGuess
         return null;
     }
 
+    /**
+     * @template T of object
+     *
+     * @param class-string<T> $class
+     *
+     * @return array{0:ClassMetadata<T>, 1:string}|null
+     */
     protected function getMetadata(string $class)
     {
         // normalize class name