prep for the production release

first pass at changelog

drop full stop from previous release notes entries

Merge pull request desktop#7699 from desktop/fix-account-identity-mis…

…match

Fix account identity mismatch

Merge pull request desktop#7693 from desktop/extra-error-context

Additional debug data in crash reports

Merge pull request desktop#7688 from desktop/fix-pr-update-crash

[Hotfix] Pull request update crash for non-db GitHubRepositories

Merge branch 'releases/the-big-one' of https://github.com/desktop/des…

…ktop into releases/the-big-one

bump version to 1.7.1-beta1

Update changelog.json

Co-Authored-By: William Shepherd <iAmWillShepherd@users.noreply.github.com>

Apply suggestions from code review

Co-Authored-By: Billy Griffin <5091167+billygriffin@users.noreply.github.com>