CI: Change the soledad test to run before webapp

It is more useful to check to see if Soledad is running before running the
webapp tests that require soledad to be running.

tests/server-tests/white-box/webapp.rb

@@ -4,6 +4,7 @@ require 'json'
 
 class Webapp < LeapTest
   depends_on "Network"
+  depends_on "Soledad"
 
   def setup
   end