fix: some repos have broken badges for last commit date

[fdsimms]

[fdsimms]

This is because many of the repos now use main instead of master branches, and badgen.net defaults to master when querying the github api for commit info.

[fdsimms]

update on this: i've opened a PR on the badgen.net repo which would fix this without any additional work on our end. so let's wait and see on this for now.