bug #32563 Container*::getServiceIds() should return strings (mathroc)

This PR was merged into the 3.4 branch.

Discussion
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Container*::getServiceIds() should return strings

| Q             | A
| ------------- | ---
| Branch?       | 4.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | o
| Tests pass?   | yes
| Fixed tickets | #32549
| License       | MIT

Cast services ids to string in `Container*::getServiceIds()`

Commits
-------

9c88caad31 Container*::getServiceIds() should return an array of string

Author: fabpot

Container.php

@@ -386,7 +386,7 @@ public function reset()
     /**
      * Gets all service ids.
      *
-     * @return array An array of all defined service ids
+     * @return string[] An array of all defined service ids
      */
     public function getServiceIds()
     {
@@ -405,7 +405,7 @@ public function getServiceIds()
         }
         $ids[] = 'service_container';
 
-        return array_unique(array_merge($ids, array_keys($this->methodMap), array_keys($this->fileMap), array_keys($this->services)));
+        return array_map('strval', array_unique(array_merge($ids, array_keys($this->methodMap), array_keys($this->fileMap), array_keys($this->services))));
     }
 
     /**

ContainerBuilder.php

@@ -815,13 +815,11 @@ public function compile(/*$resolveEnvPlaceholders = false*/)
     }
 
     /**
-     * Gets all service ids.
-     *
-     * @return array An array of all defined service ids
+     * {@inheritdoc}
      */
     public function getServiceIds()
     {
-        return array_unique(array_merge(array_keys($this->getDefinitions()), array_keys($this->aliasDefinitions), parent::getServiceIds()));
+        return array_map('strval', array_unique(array_merge(array_keys($this->getDefinitions()), array_keys($this->aliasDefinitions), parent::getServiceIds())));
     }
 
     /**