minor #51 Default shared files/dir to an empty array (javiereguiluz)

This PR was merged into the 1.0.x-dev branch.

Discussion
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Default shared files/dir to an empty array

This makes the same change as proposed by @RickSeymour in #44 ... but I couldn't fix the conflicts of his pull request, so I'm creating a new one. Thanks!

Commits
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f456373 Default shared files/dir to an empty array

src/Configuration/DefaultConfiguration.php

@@ -326,7 +326,7 @@ public function fixPermissionsWithAcl(string $webServerUser): self
     }
 
     // Relative to the project root directory
-    public function sharedFilesAndDirs(array $paths): self
+    public function sharedFilesAndDirs(array $paths = []): self
     {
         $this->sharedDirs = [];
         $this->sharedFiles = [];