Issue #3275651 by pwolanin: Fix errors on php 8.1

modules/users_jwt/src/UsersJwtKeyRepository.php

@@ -143,14 +143,15 @@ class UsersJwtKeyRepository implements UsersJwtKeyRepositoryInterface {
   /**
    * {@inheritdoc}
    */
-  public function offsetExists($offset) {
+  public function offsetExists($offset): bool {
     return (bool) $this->getKey($offset);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function offsetGet($offset) {
+  #[\ReturnTypeWillChange]
+  public function offsetGet($offset): ?string {
     $key = $this->getKey($offset);
     return $key ? $key->pubkey : NULL;
   }
@@ -158,11 +159,11 @@ class UsersJwtKeyRepository implements UsersJwtKeyRepositoryInterface {
   /**
    * {@inheritdoc}
    */
-  public function offsetSet($offset, $value) {}
+  public function offsetSet($offset, $value): void {}
 
   /**
    * {@inheritdoc}
    */
-  public function offsetUnset($offset) {}
+  public function offsetUnset($offset): void {}
 
 }

modules/users_jwt/src/UsersJwtKeyRepositoryInterface.php

@@ -85,6 +85,7 @@ interface UsersJwtKeyRepositoryInterface extends \ArrayAccess {
    * @return string|null
    *   The public key for a key ID, or null if there is no such key.
    */
-  public function offsetGet($id);
+  #[\ReturnTypeWillChange]
+  public function offsetGet($id): ?string;
 
 }