Your issue is due to insufficient directory permissions. To resolve this, change the owner of the directory accordingly:
First, you will directory user ownership to a specific non-root user using this command:
$ chown -R {user_name}:{user_group} {target_directory}
Ex: $ chown -R uvdesk:uvdesk community-skeleton
Second, add this user to the www-data apache user group using the following command:
Add user to www-data group:
$ usermod -aG {user} www-data;
Ex: $ usermod -aG uvdesk www-data;
Verify that the user has been added to the www-data group:
$ groups <your-user-name>;
Ex: $ groups uvdesk;