fix(js-sdk): skip null values in query qs.stringify (#13460)

* escape null values in qs.stringify

* skip null values

---------

Co-authored-by: William Bouchard <46496014+willbouch@users.noreply.github.com>

packages/core/js-sdk/src/client.ts

@@ -250,7 +250,7 @@ export class Client {
           const params = Object.fromEntries(
             normalizedInput.searchParams.entries()
           )
-          const stringifiedQuery = stringify({ ...params, ...init.query })
+          const stringifiedQuery = stringify({ ...params, ...init.query }, { skipNulls: true })
           normalizedInput.search = stringifiedQuery
         }
       }