rest-api-spec: fix more default values (elastic#137557) (elastic#137606)

(cherry picked from commit b850c82)

# Conflicts:
#	rest-api-spec/src/main/resources/rest-api-spec/api/indices.resolve_index.json

Author: pquentin

rest-api-spec/src/main/resources/rest-api-spec/api/cat.segments.json

@@ -96,14 +96,17 @@
       },
       "ignore_unavailable": {
         "type": "boolean",
+        "default": false,
         "description": "Whether specified concrete indices should be ignored when unavailable (missing or closed). Only allowed when providing an index expression."
       },
       "ignore_throttled": {
         "type": "boolean",
+        "default": false,
         "description": "Whether specified concrete, expanded or aliased indices should be ignored when throttled. Only allowed when providing an index expression."
       },
       "allow_no_indices": {
         "type": "boolean",
+        "default": true,
         "description": "Whether to ignore if a wildcard indices expression resolves into no concrete indices. (This includes `_all` string or when no indices have been specified). Only allowed when providing an index expression."
       },
       "expand_wildcards": {