TT#32971 Disable REST API test subscriberregistrations as it is unstable now

The code is currently broken due to the kamailio location migration
from mysql to redis. The test creates location record record using API
and it is properly created in Redis, later the test checks location
using another REST API request and find nothing:
> api-rest_api-subscriberregistrations_t.16 - subscriberregistrations:
>  create test item 'subscriberregistrations' 1
>  (Unprocessable Entity: Could not find a new registration entry in the db,
>  that might be caused by the kamailio flush mechanism,
>  where the item has been updated successfully)

The test should be re-enabled then ngcp-panel/REST code will use Redis
for location search.

Change-Id: I9706b8d04dcc2e2630d67b2622231ce726c4bc99

t/api-rest/testrunner

@@ -25,7 +25,7 @@ fi
 
 if [ "${SELECT}" = "stable" ] ; then
   echo "Test selection: ${SELECT}"
-  SELECT=$(echo ./t/api-rest/api-{all-links,balanceintervals,bannedips,bannedusers,billingfees,billingnetworks,billingprofiles,billingzones,calllists,calls,cert-auth,cfdestinationsets,contracts,customercontacts,customers,faxes,lnp,ncoslevels,pbxdevicemodels,pbxdevices,peeringgroups,peeringrules,peeringinboundrules,peeringservers,preferences,profilepackages,resellers,rewriterules,rewriterulesets,root,soundsets,subscriberregistrations,subscribers,systemcontacts,threads,topuplogs,trustedsources,valid-patch,vouchers,method-override}.t)
+  SELECT=$(echo ./t/api-rest/api-{all-links,balanceintervals,bannedips,bannedusers,billingfees,billingnetworks,billingprofiles,billingzones,calllists,calls,cert-auth,cfdestinationsets,contracts,customercontacts,customers,faxes,lnp,ncoslevels,pbxdevicemodels,pbxdevices,peeringgroups,peeringrules,peeringinboundrules,peeringservers,preferences,profilepackages,resellers,rewriterules,rewriterulesets,root,soundsets,subscribers,systemcontacts,threads,topuplogs,trustedsources,valid-patch,vouchers,method-override}.t)
 elif [ "${SELECT}" = "fast" ] ; then
   echo "Test selection: ${SELECT}"
   SELECT=$(echo ./t/api-rest/api-{bannedips,bannedusers,billingnetworks,billingzones,calls,cert-auth,cfdestinationsets,ncoslevels,peeringgroups,peeringrules,peeringinboundrules,peeringservers,resellers,rewriterules,root,soundsets,systemcontacts,valid-patch,vouchers,method-override}.t)