docs: improve Go documentation (#7820)

* use 1.'s for ordered list

* fix whitespace in ordered list

* use active voice

* capitalize SemVer

* Remove fluff word

* use active voice

* update paragraph, needs further work

* explain how to pin to a specific Go lang version

* change Go version from 1.14.2 -> 1.14.12

* strip patch level from Go version, explain why