Fix test - times can be 0 sometimes (#115260) (#115268)

(cherry picked from commit ffcd62e)

Author: smalyshev

rest-api-spec/src/yamlRestTest/resources/rest-api-spec/test/cluster.stats/30_ccs_stats.yml

@@ -121,10 +121,10 @@
   - is_true: ccs._search.total
   - is_true: ccs._search.success
   - exists: ccs._search.skipped
-  - is_true: ccs._search.took
-  - is_true: ccs._search.took.max
-  - is_true: ccs._search.took.avg
-  - is_true: ccs._search.took.p90
+  - exists: ccs._search.took
+  - exists: ccs._search.took.max
+  - exists: ccs._search.took.avg
+  - exists: ccs._search.took.p90
   - is_true: ccs._search.took_mrt_true
   - exists: ccs._search.took_mrt_true.max
   - exists: ccs._search.took_mrt_true.avg
@@ -145,7 +145,7 @@
   - gte: {ccs._search.clusters.cluster_two.total: 1}
   - exists: ccs._search.clusters.cluster_one.skipped
   - exists: ccs._search.clusters.cluster_two.skipped
-  - is_true: ccs._search.clusters.cluster_one.took
-  - is_true: ccs._search.clusters.cluster_one.took.max
-  - is_true: ccs._search.clusters.cluster_one.took.avg
-  - is_true: ccs._search.clusters.cluster_one.took.p90
+  - exists: ccs._search.clusters.cluster_one.took
+  - exists: ccs._search.clusters.cluster_one.took.max
+  - exists: ccs._search.clusters.cluster_one.took.avg
+  - exists: ccs._search.clusters.cluster_one.took.p90