Many awesome PRs merged

This release includes quite a few PRs that were opened while I had been away from open source for a while - Thanks everyone for your contributions and patience as I get back in the groove of maintaining my open source repos!

This release adds:

• UsersClient to access user provisioning via @sangaline (#114)
• ability to PATCH an engagement in the EngagementsClient via @FredrikWendt (#119)

This release fixes:

• type hints of companies.search_domain via @jeking3 (#102)
• pickling HubspotError by adding a __reduce__() via @jeking3 (#103)
• excessive log output and potential token exposure via @robinpercy (#113)
• sensitive data appearing in the logs via @dpgaspar (#117)
• typing_extensions no longer required as of python 3.8 via @singingwolfboy (#118)