fix(UserIT): user is forbidden to change role

src/test/java/ch/unige/solidify/auth/UserIT.java

@@ -96,10 +96,10 @@ class UserIT {
     final ResponseEntity<String> response = restClient.post()
             .uri(USER_ENDPOINT + USER_CHANGE_ROLE_ENDPOINT, TEST_USER_EXTERNAL_UID)
             .headers(headers -> headers.setBearerAuth(oAuth2Token))
+            .body("USER")
             .retrieve()
             .onStatus(status -> true, (req, resp) -> {})
             .toEntity(String.class);
-    // TODO: Fix this
-    assertEquals(HttpStatus.BAD_REQUEST, response.getStatusCode());
+    assertEquals(HttpStatus.FORBIDDEN, response.getStatusCode());
   }
 }