Add doc support for delete-from-store API

It is observed that the api-ref has no doc support for
delete-from-store (/v2/stores/%(store)s/%(image)s) API.
This patch adds the doc support for delete-from-store in api-ref.

bp: delete-from-store

Closes-Bug: #1941038
Change-Id: I5e82ff9f979b80b5b1e06eebea84a1b2fb50c78e

api-ref/source/v2/images-parameters.yaml

@@ -104,6 +104,12 @@ member_id-in-path:
   in: path
   required: true
   type: string
+store-in-path:
+  description: |
+    The ID of the store from which image is to be deleted.
+  in: path
+  required: true
+  type: string
 tag-in-path:
   description: |
     The image tag.  A tag is limited to 255 chars in length.  You may wish

api-ref/source/v2/index.rst

@@ -29,6 +29,7 @@ Image Service API v2 (CURRENT)
 .. include:: images-schemas.inc
 .. include:: images-data.inc
 .. include:: images-import.inc
+.. include:: stores.inc
 .. include:: discovery.inc
 .. include:: tasks.inc
 .. include:: tasks-schemas.inc

api-ref/source/v2/stores.inc

@@ -0,0 +1,30 @@
+.. -*- rst -*-
+
+Stores
+******
+
+Multi-store backend support allows for storing copies of an image in multiple places.
+
+Delete image from store
+~~~~~~~~~~~~~~~~~~~~~~~
+
+.. rest_method::  DELETE /v2/stores/{store_id}/{image_id}
+
+This API allows you to delete a copy of the image from a specific store.
+*(Since Image API v2.10)*
+
+.. note::
+    * This API will not allow deletion of the last location for an image.
+
+Normal response codes: 204
+
+Error response codes: 400, 401, 403, 404, 409
+
+Request
+-------
+
+.. rest_parameters:: images-parameters.yaml
+
+   - store_id: store-in-path
+   - image_id: image_id-in-path
+