Tests that console properly displays BigInts.

console-format-bigint.js:15 1n
console-format-bigint.js:16 BigInt {2n}
console-format-bigint.js:17 [1n]
console-format-bigint.js:18 [BigInt]
console-format-bigint.js:19 null 1n BigInt {2n}
console-format-bigint.js:20 123n 123n 123n 123n
Expanded all messages
console-format-bigint.js:15 1n
console-format-bigint.js:16 BigInt {2n}
    __proto__: BigInt
    [[PrimitiveValue]]: 2n
console-format-bigint.js:17 [1n]
    0: 1n
    length: 1
    __proto__: Array(0)
console-format-bigint.js:18 [BigInt]
    0: BigInt {2n}
    length: 1
    __proto__: Array(0)
console-format-bigint.js:19 null 1n BigInt {2n}
    __proto__: BigInt
    [[PrimitiveValue]]: 2n
console-format-bigint.js:20 123n 123n 123n 123n