Spire - v1.6.0

Added:
- Support for customization of SVID and CA attributes through CredentialComposer plugins (#3819, #3832, #3862, #3869)
- Experimental support to validate container images signatures through sigstore selectors (#3159)
- Published scratch images now support ARM64 architecture (#3607)
- Published scratch images are now signed using Sigstore (#3707)
- spire-server mint and spire-server token generate CLI commands now support the -output flag (#3800)
- spire-agent api CLI command now supports the -output flag (#3818)
- Release images now include a non-root user and default folders (#3811)
- Agent accepts bootstrap bundles in SPIFFE format (#3753)
- Database index for registration entry hint column (#3828)

Changed:
- Plugins are configured and executed in the order they are defined (#3797)
- Documentation improvements (#3826, #3842, #3870)

Fixed:
- Server crash when authorization layer was unable to talk to the datastore (#3829)
- Timestamps in logs are now consistently in local time (#3734)
- Removed
- Non-scratch images are no longer published (#3785)
- k8s-workload-registar is no longer released and maintained (#3853)
- Unused database column x509_svid_ttl from registered_entries table (#3808)
- The deprecated enabled flag from InMem telemetry config (#3796)
- The deprecated default_svid_ttl configurable (#3795)
- The deprecated omit_x509svid_uid configurable (#3794)