docs: added docs for reset password (#9306)

- Added to docs on implementing auth flows using the module and API routes how to update a user's password
- Added guide on how to send a notification when a password token is generated
- Added a guide on implementing reset password flow in storefront
- Added OAS for the `/update` and `/reset-password` routes + generated specs for the API reference

www/apps/api-reference/specs/store/code_samples/Shell/auth_customer_{auth_provider}_reset-password/post.sh

@@ -0,0 +1,5 @@
+curl -X POST '{backend_url}/auth/customer/emailpass/reset-password' \
+-H 'Content-Type: application/json' \
+--data-raw '{
+  "identifier": "customer@gmail.com"
+}'

www/apps/api-reference/specs/store/code_samples/Shell/auth_customer_{auth_provider}_update/post.sh

@@ -0,0 +1,6 @@
+curl -X POST '{backend_url}/auth/customer/emailpass/update?token=123' \
+-H 'Content-Type: application/json' \
+--data-raw '{
+  "email": "customer@gmail.com",
+  "password": "supersecret"
+}'