Amend HSM cert usage (sigstore#151)

There was an issue with invalid key types when verifying
cosign signed registry sigs with a fulcio cert generated using
the fuclio createca command

This PR makes the resulting createca generated cert have partity
to GCA generated certs

The result is a HSM / createca root cert can be used to both sign
and verify registry entries

Resolves: sigstore#150

Signed-off-by: Luke Hinds <[email protected]>

Bump github.com/spf13/cobra from 1.2.0 to 1.2.1 (sigstore#137)

Bumps [github.com/spf13/cobra](https://github.com/spf13/cobra) from 1.2.0 to 1.2.1.
- [Release notes](https://github.com/spf13/cobra/releases)
- [Changelog](https://github.com/spf13/cobra/blob/master/CHANGELOG.md)
- [Commits](spf13/cobra@v1.2.0...v1.2.1)

---
updated-dependencies:
- dependency-name: github.com/spf13/cobra
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>