pr-9551.md

Fix prettier-ignored mapped types (#9551 by @fisker)

// Input
type a= {
    // prettier-ignore
    [A in B]: C  |  D
  }

// Prettier stable
type a = {
  // prettier-ignore
  A in B: C | D;
};

// Prettier master
type a = {
    // prettier-ignore
    [A in B]: C  |  D
  };