support for image signatures and some bugfixes

What's Changed

• revert release workflow by @rchincha in #276
• Fix data races in tests, closes #255 by @adodon2go in #274
• go.mod: upgrade module deps by @rchincha in #277
• ci/cd: update badges link to refer to main branch by @shimish2 in #284
• dependabot: fix dependabot alerts by @rchincha in #287
• go.mod: tidy go.mod by @rchincha in #289
• go.mod: fix another dependabot alert by @rchincha in #290
• routes: fix CheckManifest to return content length by @rchincha in #288
• sync: skip tls verify on /v2/_catalog when a registry is configured w… by @peusebiu in #285
• Sync prefix can be an exact match or a glob pattern, closes #297 by @peusebiu in #298
• ci/cd: unit test hangs for a long time intermittently closes #286 by @adodon2go in #291
• ci/cd: keep docker and stacker builds files consistent by @rchincha in #301
• artifacts: initial support for artifacts spec by @rchincha in #265

Full Changelog: v1.3.3...v1.3.4