[ci] Review `cargo-semver-checks` Github Action workflows, find gaps related to feature resolution & re-exports of workspace dependencies

Context: https://github.com/awslabs/aws-lambda-rust-runtime/issues/1023

We had semver breakage in a `lambda_http` patch release due to its dependency on `aws_lambda_events`.

My understanding was that our CI should have failed this. We should find whether there is a gap in our CI setup, or a bug in `cargo-semver-issues`.