fix(tests): make mocks for rest octokit async

tests/mocks/api/github/rest/users/getByUsername.mjs

@@ -1,5 +1,5 @@
 /**Mocked data */
-export default function({ faker }, target, that, [{ username }]) {
+export default async function({ faker }, target, that, [{ username }]) {
   console.debug("metrics/compute/mocks > mocking rest api result > rest.repos.getByUsername")
   return ({
     status: 200,

tests/mocks/api/github/rest/users/listGpgKeysForUser.mjs

@@ -1,5 +1,5 @@
 /**Mocked data */
-export default function({ faker }, target, that, [{ username }]) {
+export default async function({ faker }, target, that, [{ username }]) {
   console.debug("metrics/compute/mocks > mocking rest api result > rest.users.listGpgKeysForUser")
   return ({
     status: 200,