perf(NODE-6126): improve Long.fromBigInt performance

[aditi-khare-mongoDB]

Description

Refactor Long.fromBigInt to only use bit math, and refactor the Long constructor to have cleaner logic + remove Object.assign calls

What is changing?

Improve performance of Long.fromBigInt

Is there new documentation needed for these changes?

No.

What is the motivation for this change?

Use a more efficient algorithm for Long.fromBigInt

Release Highlight

Optimize performance of Long.fromBigInt

Internally fromBigInt was originally implemented using toString of the bigint value. Now, Long.fromBigInt has been refactored to use bitwise operations greatly improving performance.

Double check the following

• Ran npm run check:lint script
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[aditi-khare-mongoDB]

Link to perf sheet

Chose BigInt Constructor because it is 7.2% better than the 10,000 iterations case for FromString/ToString, and 1.4% improvement from the BigInt Literal case

[nbbeeken]

comment about !, req changes for viz