time: optimise time.GoString

[amarjeetanandsingh]

Currently Time.GoString uses methods like Year(), Month(), Day() to generate the string. These methods call absDate() internally. We can improve the performance by avoiding multiple calls to absDate().

[gopherbot]

Change https://go.dev/cl/423634 mentions this issue: time: optimise GoString

[amarjeetanandsingh]

cc @ianlancetaylor @dsnet

[AAlvarez90]

@amarjeetanandsingh Thanks for your contribution and observations. Although this issue was addressed somewhere else, we appreciate the time you took to look into a potential improvement here. Well done, mate.