fixtures.yml: Delete legacy symlink

puppetlabs_spec_helper will create the symlink for us, we don't need it
in .fixtures.yml.

Author: bastelfreak

.fixtures.yml

@@ -5,5 +5,3 @@ fixtures:
     "facts": "https://github.com/puppetlabs/puppetlabs-facts.git"
     "puppet_agent": "https://github.com/puppetlabs/puppetlabs-puppet_agent.git"
     "provision": "https://github.com/puppetlabs/provision.git"
-  symlinks:
-    "mysql": "#{source_dir}"