Implement ES2024 Object.groupBy

[robik]

Summary

This PR implements ES2024 Object.groupBy function.

Test Plan

Added tests

$ echo "Object.groupBy([1, 2, 3, 4, 5, 6, 7], key => key)" | ./hermes
>> { 1: [ 1, [length]: 1 ], 2: [ 2, [length]: 1 ], 3: [ 3, [length]: 1 ], 4: [ 4, [length]: 1 ], 5: [ 5, [length]: 1 ], 6: [ 6, [length]: 1 ], 7: [ 7, [length]: 1 ] }