async function ensureUnmountByUrl (pathSelector, url, drive) {
  try {
    let mounts = await drive.query({
      path: pathSelector,
      mount: url
    })
    if (mounts[0]) {
      // remove mount
      await drive.unmount(mounts[0].path)
    } else {
      throw "Mount not found"
    }
  } catch (e) {
    console.error('Filesystem failed to unmount drive', {pathSelector, url, error: e})
  }
}
@param {string} pathSelector 
@param {string} url
@param {Object} drive
@return {Promise<void>}