fix(medusa): Use correct auth middleware in GET /store/auth (#2687)

* use correct authentication middleware

* remove guard from get-session since it's guarded by middleware doing the same check

* Add integration tests

* Create lazy-swans-agree.md

Co-authored-by: olivermrbl <oliver@mrbltech.com>
Co-authored-by: Oliver Windall Juhl <59018053+olivermrbl@users.noreply.github.com>

.changeset/lazy-swans-agree.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/medusa": patch
+---
+
+fix(medusa): Use requireCustomerAuthentication middleware in get-session