Support spent date when adding spent time for an issue using the API

Description

When using tools to automate time tracking, it is really limited as the API doesn't allow to send spent date when adding spent time for an issue. Currently using the api with automation tools, This is a problem if you enter your spent time not on the same day when they were actually spent.

Proposal

Support spent_date parameter for endpoint POST /projects/:id/issues/:issue_iid/add_spent_time

Links / references

https://docs.gitlab.com/ee/api/issues.html#add-spent-time-for-an-issue

https://github.com/kriskbx/gitlab-time-tracker/issues/39

Edited by Mohamed Fattouh