32f9b1a231 ci: gate coverage analysis on whether source code changed (Andrew Poelstra)
2203c02347 ci: gate fuzztesting on whether source code changed (Andrew Poelstra)
09f7fc3cff ci: gate CI workflow on source being changed (Andrew Poelstra)
9aca8a18c7 ci: introduce `classify-pr.sh` script which determines whether a PR should have CI run (Andrew Poelstra)
Pull request description:
Fixes#2523
ACKs for top commit:
tcharding:
ACK 32f9b1a231
Tree-SHA512: 7d53365bdf4e8ae5480221e43b4c515d4b16048ec1a00cb62ab65b2d2b91a37f8945c39b619a82bfe4ca74f3508176d9879481b908bb8d3fe8d214b173d3bf18