Use english locale for tests and docs (#113671)

English doesn't change between JDK 22 and 23

Author: thecoop

docs/reference/search/search-your-data/search-your-data.asciidoc

@@ -124,7 +124,7 @@ GET /my-index-000001/_search
       "script": {
         "source":
         """emit(doc['@timestamp'].value.dayOfWeekEnum
-        .getDisplayName(TextStyle.FULL, Locale.ROOT))"""
+        .getDisplayName(TextStyle.FULL, Locale.ENGLISH))"""
       }
     }
   },

x-pack/plugin/eql/qa/rest/src/yamlRestTest/resources/rest-api-spec/test/eql/10_basic.yml

@@ -13,7 +13,7 @@ setup:
                 day_of_week:
                   type: keyword
                   script:
-                    source: "emit(doc['@timestamp'].value.dayOfWeekEnum.getDisplayName(TextStyle.FULL, Locale.ROOT))"
+                    source: "emit(doc['@timestamp'].value.dayOfWeekEnum.getDisplayName(TextStyle.FULL, Locale.ENGLISH))"
   - do:
       bulk:
         refresh: true

x-pack/plugin/eql/qa/rest/src/yamlRestTest/resources/rest-api-spec/test/eql/20_runtime_mappings.yml

@@ -9,7 +9,7 @@ setup:
                 day_of_week:
                   type: keyword
                   script:
-                    source: "emit(doc['@timestamp'].value.dayOfWeekEnum.getDisplayName(TextStyle.FULL, Locale.ROOT))"
+                    source: "emit(doc['@timestamp'].value.dayOfWeekEnum.getDisplayName(TextStyle.FULL, Locale.ENGLISH))"
   - do:
       bulk:
         refresh: true