Use acts_as_taggable for investment valuation tags

We were manually doing the same thing, generating inconsistent results,
since the method `valuation_tag_list` was using the `valuation` context,
when actually the expected behavior would be to use the `valuation_tag`
context.

lib/tasks/consul.rake

@@ -4,6 +4,7 @@ namespace :consul do
 
   desc "Runs tasks needed to upgrade from 1.0.0 to 1.1.0"
   task "execute_release_1.1.0_tasks": [
-    "budgets:set_original_heading_id"
+    "budgets:set_original_heading_id",
+    "migrations:valuation_taggings"
   ]
 end