splitting upgrade api specs (#703)

Signed-off-by: Tokesh <tokesh789@gmail.com>

tests/default/_core/upgrade.yaml

@@ -0,0 +1,20 @@
+$schema: ../../../json_schemas/test_story.schema.yaml
+
+description: Test upgrading indices using both GET and POST methods.
+chapters:
+  - synopsis: Trigger upgrade (POST).
+    path: /_upgrade
+    method: POST
+    request:
+      payload:
+        allow_no_indices: false
+        expand_wildcards: closed
+        ignore_unavailable: false
+    response:
+      status: 200
+
+  - synopsis: Check upgrade status (GET).
+    path: /_upgrade
+    method: GET
+    response:
+      status: 200

tests/default/indices/upgrade.yaml

@@ -36,22 +36,5 @@ chapters:
     method: GET
     parameters:
       index: [movies]
-    response:
-      status: 200
-
-  - synopsis: Trigger upgrade (POST).
-    path: /_upgrade
-    method: POST
-    request:
-      payload:
-        allow_no_indices: false
-        expand_wildcards: closed
-        ignore_unavailable: false
-    response:
-      status: 200
-
-  - synopsis: Check upgrade status (GET).
-    path: /_upgrade
-    method: GET
     response:
       status: 200