fix(stackable-webhook): Avoid aws-lc-rs crate, as it fails in nix

[sbernauer]

Description

Hopefully one day we are able to build aws-lc-rs on nix: nix-community/crate2nix#376

cargo tree | grep aws now is empty, make run-dev works.

Definition of Done Checklist

• Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant
• Please make sure all these things are done and tick the boxes

# Author
- [ ] Changes are OpenShift compatible
- [ ] CRD changes approved
- [ ] Integration tests passed (for non trivial changes)

# Reviewer
- [ ] Code contains useful comments
- [ ] (Integration-)Test cases added
- [ ] Documentation added or updated
- [ ] Changelog updated
- [ ] Cargo.toml only contains references to git tags (not specific commits or branches)

# Acceptance
- [ ] Feature Tracker has been updated
- [ ] Proper release label has been added