Fix new synthetic source copy_to tests to pass on serverless (#113320)

Author: lkts

rest-api-spec/src/yamlRestTest/resources/rest-api-spec/test/indices.create/20_synthetic_source.yml

@@ -1815,6 +1815,8 @@ synthetic_source with copy_to pointing at dynamic field:
             _source:
               mode: synthetic
             properties:
+              name:
+                type: keyword
               k:
                 type: keyword
                 copy_to: c.copy
@@ -1829,6 +1831,7 @@ synthetic_source with copy_to pointing at dynamic field:
         id: 1
         refresh: true
         body:
+          name: "A"
           k: "hello"
 
   - do:
@@ -1837,6 +1840,7 @@ synthetic_source with copy_to pointing at dynamic field:
         id: 2
         refresh: true
         body:
+          name: "B"
           k: ["55", "66"]
 
   - do:
@@ -1845,32 +1849,37 @@ synthetic_source with copy_to pointing at dynamic field:
         id: 3
         refresh: true
         body:
+          name: "C"
           k: "hello"
           c:
             copy: "zap"
 
   - do:
       search:
         index: test
+        sort: name
         body:
           docvalue_fields: [ "c.copy.keyword" ]
 
   - match:
       hits.hits.0._source:
+        name: "A"
         k: "hello"
   - match:
       hits.hits.0.fields:
         c.copy.keyword: [ "hello" ]
 
   - match:
       hits.hits.1._source:
+        name: "B"
         k: ["55", "66"]
   - match:
       hits.hits.1.fields:
         c.copy.keyword: [ "55", "66" ]
 
   - match:
       hits.hits.2._source:
+        name: "C"
         k: "hello"
         c:
           copy: "zap"
@@ -1892,6 +1901,8 @@ synthetic_source with copy_to pointing inside dynamic object:
             _source:
               mode: synthetic
             properties:
+              name:
+                type: keyword
               k:
                 type: keyword
                 copy_to: c.copy
@@ -1902,6 +1913,7 @@ synthetic_source with copy_to pointing inside dynamic object:
         id: 1
         refresh: true
         body:
+          name: "A"
           k: "hello"
 
   - do:
@@ -1910,6 +1922,7 @@ synthetic_source with copy_to pointing inside dynamic object:
         id: 2
         refresh: true
         body:
+          name: "B"
           k: ["55", "66"]
 
   - do:
@@ -1918,32 +1931,37 @@ synthetic_source with copy_to pointing inside dynamic object:
         id: 3
         refresh: true
         body:
+          name: "C"
           k: "hello"
           c:
             copy: "zap"
 
   - do:
       search:
         index: test
+        sort: name
         body:
           docvalue_fields: [ "c.copy.keyword" ]
 
   - match:
       hits.hits.0._source:
+        name: "A"
         k: "hello"
   - match:
       hits.hits.0.fields:
         c.copy.keyword: [ "hello" ]
 
   - match:
       hits.hits.1._source:
+        name: "B"
         k: ["55", "66"]
   - match:
       hits.hits.1.fields:
         c.copy.keyword: [ "55", "66" ]
 
   - match:
       hits.hits.2._source:
+        name: "C"
         k: "hello"
         c:
           copy: "zap"