No space after colon of ternary operator in array literal

Input:
```D
const x = [0 ? 1 : 2];
const y = 0 ? 1 : 2;
```

Expected output: the same.
Actual dfmt output:
```D
const x = [0 ? 1: 2];
const y = 0 ? 1 : 2;
```

dfmt removes the space after the 1 in the array. Perhaps it's formatting it like an array index designator.
