Convert put_template uses to put_script in rest tests

Original commit: elastic/x-pack-elasticsearch@5f5f52b955

qa/smoke-test-security-with-mustache/src/test/resources/rest-api-spec/test/10_templated_role_query.yml

@@ -93,14 +93,19 @@ setup:
             }
 
   - do:
-      put_template:
+      put_script:
         id: "1"
         body: >
             {
+              "script": {
+                "lang": "mustache",
+                "source": {
                   "term" : {
                     "username" : "{{_user.username}}"
                   }
                 }
+              }
+            }
 
   - do:
       index:

qa/smoke-test-security-with-mustache/src/test/resources/rest-api-spec/test/11_templated_role_query_runas.yml

@@ -93,14 +93,19 @@ setup:
             }
 
   - do:
-      put_template:
+      put_script:
         id: "1"
         body: >
             {
+              "script": {
+                "lang": "mustache",
+                "source": {
                   "term" : {
                     "username" : "{{_user.username}}"
                   }
                 }
+              }
+            }
 
   - do:
       index:

qa/smoke-test-watcher-with-mustache/src/test/resources/rest-api-spec/test/watcher_mustache/30_search_input.yml

@@ -102,9 +102,12 @@ setup:
 "Test search input mustache integration (using request template)":
 
   - do:
-      put_template:
+      put_script:
         id: "search-template"
         body: {
+                "script": {
+                  "lang": "mustache",
+                  "source": {
                     "query" : {
                       "bool" : {
                         "must" : [
@@ -117,6 +120,8 @@ setup:
                       }
                     }
                   }
+                }
+              }
   - match: { acknowledged: true }
 
   - do: