Fixed last remaining Psalm issue

Author: matthewbdaly

psalm-baseline.xml

@@ -1,8 +1,2 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<files psalm-version="4.23.0@f1fe6ff483bf325c803df9f510d09a03fd796f88">
-  <file src="src/AzureStorageServiceProvider.php">
-    <MixedArgumentTypeCoercion occurrences="1">
-      <code>$config</code>
-    </MixedArgumentTypeCoercion>
-  </file>
-</files>
+<files psalm-version="4.23.0@f1fe6ff483bf325c803df9f510d09a03fd796f88"/>

src/AzureStorageServiceProvider.php

@@ -73,6 +73,7 @@ public function register()
             $configObject = $app->make('config');
             assert($configObject instanceof \Illuminate\Contracts\Config\Repository);
             $config = empty($config) ? (array)$configObject->get('filesystems.disks.azure') : $config;
+            /** @var ProviderConfig $config */
 
             if (!empty($config['connection_string'])) {
                 $endpoint = (string)$config['connection_string'];