Flags for specifying sets of features to separately run cargo-semver-check on

By default, cargo-semver-checks will enable all features except those with a name hinting they are unstable. See https://github.com/obi1kenobi/cargo-semver-checks?tab=readme-ov-file#what-features-does-cargo-semver-checks-enable-in-the-tested-crates

We have some crates where 2 features are mutually exclusive and will fail to compile if both enabled, or else can be compiled together but one effectively overrides the other which is not applied. For example: https://github.com/holochain/kitsune2/pull/393/files#diff-7d26d38cbdff87a841895d39d1f1f274c6fd51b2003e6c0ff08e8785d843a22dR58

To validate semver for this crates, we will need to run the cargo-semver-checks multiple times, each time with only specific features enabled.

AC:
- Add a flag `--feature-set` which can be included multiple times, each with a distinct list of features. I.e. `--feature-set ",," --feature-set ",,"`
- Run cargo-semver-checks separately for each feature-set