v6.0.0

BumpStdlibs v6.0.0

Diff since v5.1.0

Closed issues:

• Feature request: Support updating non-master julia branches, like release-1.8 (#76)
• Don't close PRs for different branches (#87)
• Add a link to the github diff (#90)

Merged pull requests:

• Display and check if julia & stdlib versions match (#80) (@IanButterworth)
• Support updating non-master Julia branches (such as backports-release-1.9) (#83) (@DilumAluthge)
• Only run CI on Julia v1 and Julia nightly (#84) (@DilumAluthge)
• tweak to version printing (#85) (@IanButterworth)
• Convert AbstractStrings to Strings (#86) (@DilumAluthge)
• Only close old PRs if they have the same target branch as the current run (#88) (@DilumAluthge)
• Use Bors to control that only one integration test is running at a time (#89) (@DilumAluthge)
• Add a link to the GitHub diff (#91) (@DilumAluthge)