v0.6.0

This was a security release where the main focus was hardening SPIKE SDK mTLS
implementation. In addition, we created a configurable SPIKE backing store
directory to enable future HA development.

The code is stable; however, we are marking it as a "prerelease" because there is still
upstream Helm Charts work to be completed to smoothly enable SPIKE Bootstrap
on Kubernetes clusters.

Added

• Added SPIKE_TRUST_ROOT_BOOTSTRAP to enable SPIKE Bootstrap to be used
  in different trust boundaries.
• Added SPIKE_NEXUS_DATA_DIR to enable setting up custom data directories for
  SPIKE Nexus backing store.
• Added convenience methods to the SPIKE Go SDK.

Changed

• Improvements to the SPIKE Go SDK.
• Stricter SPIFFE ID validation. SPIKE SDK now ensures that the API client
  only talks to SPIKE Nexus as the server.

Fixed

• Minor bug fixes.
• Fixed flaky unit tests.

Security

• SPIKE Go SDK clients are hardened to only talk to SPIKE Nexus as the
  server during mTLS.

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Below are the generated release notes of every commit since the last release cut:

What's Changed

• Configurable data directory for SPIKE Nexus backing store by @v0lkan in #232

Full Changelog: v0.5.1...v0.6.0