Apply fixes from StyleCI (#65)

Author: denpamusic

Diff for: src/Traits/ImmutableArray.php

@@ -56,4 +56,4 @@ public function offsetGet($offset): mixed
     {
         return $this->toArray()[$offset] ?? null;
     }
-}
+}

Diff for: src/Traits/SerializableContainer.php

@@ -36,7 +36,7 @@ public function unserialize($serialized): void
     public function __serialize(): array
     {
         return [
-            'container' => $this->toContainer()
+            'container' => $this->toContainer(),
         ];
     }
 
@@ -59,4 +59,4 @@ public function jsonSerialize(): array
     {
         return $this->toContainer();
     }
-}
+}