[TEST] decreased number of replicas to 0 in refresh tests

Some tests disable refresh and verify that documents cannot be found without an explicit refresh. With at least one replica and waiting for yellow though, it can happen that we start indexing docs when the replicas are not ready yet, and as soon as they become ready they get refreshed, causing the newly added docs to be unexpectedly found. Solution is to disable replicas for these specific tests.

rest-api-spec/test/create/60_refresh.yaml

@@ -7,6 +7,7 @@
           body:
               settings:
                   index.refresh_interval: -1
+                  number_of_replicas: 0
  - do:
       cluster.health:
           wait_for_status: yellow

rest-api-spec/test/index/60_refresh.yaml

@@ -7,6 +7,7 @@
           body:
               settings:
                   index.refresh_interval: -1
+                  number_of_replicas: 0
  - do:
       cluster.health:
           wait_for_status: yellow

rest-api-spec/test/update/60_refresh.yaml

@@ -7,6 +7,7 @@
           body:
               settings:
                   index.refresh_interval: -1
+                  number_of_replicas: 0
  - do:
       cluster.health:
           wait_for_status: yellow