feat: add 'exec and check' helper

useful for re-executing some function if the expected result isn't found

src/lib/exec_and_check.mjs

@@ -0,0 +1,21 @@
+export default async function execAndCheck(fn, test, onFailure = () => {}, opts = { tries: 3 }) {
+  let count = 0;
+
+  const tryExec = async () => {
+    // exec function
+    await fn();
+
+    // check test function result (pass/fail)
+    const res = await test();
+    if (res) return;
+
+    // if retry limit is hit, call failure function
+    count += 1;
+    if (count >= opts.tries) return onFailure(); // eslint-disable-line consistent-return
+
+    // retry the function and retest the results
+    return tryExec(); // eslint-disable-line consistent-return
+  };
+
+  return tryExec();
+}