Flatten object literal with other objects (without knowing property names)

flaten.ts

const typography = {
  primary: {
    family: "Lato"
  },
  secondary: {
    family: "Roboto"
  }
};

const aliases = Object.entries(typography)
  .map((o) => {
    return { [o[0]]: o[1].family };
  })
  .reduce((v, i) => Object.assign({}, v, i));

/*
Output: 
{
  "primary": "Lato",
  "secondary": "Roboto"
} 
*/