test: extend jest timeouts (#9062)

lib/manager/git-submodules/extract.spec.ts

@@ -11,6 +11,9 @@ const Git: typeof _simpleGit = jest.requireActual('simple-git');
 const localDir = `${__dirname}/__fixtures__`;
 
 describe('lib/manager/gitsubmodules/extract', () => {
+  // flaky ci tests
+  jest.setTimeout(10 * 1000);
+
   beforeAll(() => {
     simpleGit.mockImplementation((basePath: string) => {
       const git = Git(basePath);