Fix snippets in upgrade docs
The upgrade docs were using the json language tag but console wants
these to be js for proper formatting. This commit addresses that.
@@ -83,7 +83,7 @@ collection after the upgrade to use monitoring. Set
`xpack.monitoring.collection.enabled` to `true` with the `_cluster/settings`
API:
-[source,json]
+[source,js]
----------------------------------------------------------
PUT /_cluster/settings
{
@@ -97,7 +97,7 @@ PUT /_cluster/settings
To take all of the {xpack} features for a spin, you can start a 30-day trial
from Kibana, or with the Start Trial API:
-[source,json]
+[source,js]
----------------------------------------------------------
POST _xpack/license/start_trial
----------------------------------------------------------
