Added annotate-metadata command

[Yaxhveer]

Description of the PR

Added annotate-metadata command in cli allowing users to add hasMetadata attestation for subject to the graph. Format: guacone annotate-metadata [flags] <type> <subject> <key> <value>. Fixes: #1710

PR Checklist

• [x] All commits have a Developer Certificate of Origin (DCO) -- they are generated using -s flag to git commit.
• [ ] All CI checks are passing (tests and formatting)

[pxp928]

Thanks @Yaxhveer! We will review this soon!