[targets v11] What to do with the GitHub TSA in trusted_root.json

[kommendorkapten]

Description

Currently we ship GitHub's TSA as part of trusted_root.json

This was made in an effort to support the community and possibly the npm work with a TSA, but it's not used outside of GitHub to my knowledge.

The certificate for GitHub's TSA have now been rotated, and the rotation frequency is currently every 6 months (yes this is frequent!). This will pose a challenge for sigstore root signing to keep up.

I'm thinking if we should remove the TSA from trusted_root.json?

cc @trevrosen @bobcallaway @haydentherapper

[haydentherapper]

I’m unaware of anyone using it as well. SGTM

[haydentherapper]

@jku fyi related to what we were chatting about, we can remove this as part of the next rotation

[jku]

Test in staging ongoing in sigstore/root-signing-staging#157