Remove default from schema, let it be handled in code

Author: SimonUnge

deps/rabbit/priv/schema/rabbit.schema

@@ -1653,7 +1653,6 @@ end}.
 %%
 
 {mapping, "verify_initial_run", "rabbit.verify_initial_run", [
-    {default, false},
     {datatype, {enum, [true, false]}}
 ]}.