feat(typescript): support TSImportType

[ikatyang]

Ref: microsoft/TypeScript#22592

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Prettier pr-4429
Playground link

--parser typescript

Input:

export const x:import(   "./foo"   )={x:0,y:0};

export let y:import("./foo2"   ).Bar.I={a:"",b:0};

export let shim:typeof import(   "./foo2")={Bar: Bar2};

Output:

export const x: import("./foo") = { x: 0, y: 0 };

export let y: import("./foo2") = { a: "", b: 0 };

export let shim: import("./foo2") = { Bar: Bar2 };

[j-f1]

Can you add another run_spec with singleQuote: true?