message: auth-backend: explicit pickBy type
diff: @@ -36,7 +36,7 @@ export const readState = (stateString: string): OAuthState => {
  export const encodeState = (state: OAuthState): string => {
  const stateString = new URLSearchParams(
  - pickBy(state, value => value !== undefined),
  + pickBy<string>(state, value => value !== undefined),
  ).toString();
  return Buffer.from(stateString, 'utf-8').toString('hex');
  