fix(ci): add target_commitish to release payload to fix HTTP 500

The publish-release job was missing the target_commitish field in the
Gitea release creation API payload. Without it, Gitea cannot resolve
the tag to a git object and returns HTTP 500 with 'object does not
exist'.

Add COMMIT_SHA (from github.sha) to the job env and pass it as
target_commitish in the JSON payload.

Closes #326

.gitea/workflows/release.yml

@@ -322,6 +322,7 @@ jobs:
 
     env:
       BUILD_TAG: ${{ github.ref_name || inputs.tag }}
+      COMMIT_SHA: ${{ github.sha }}
       NODE_EXTRA_CA_CERTS: /etc/ssl/certs/ca-certificates.crt
 
     steps:
@@ -386,6 +387,7 @@ jobs:
               'name': f'Kindred Create {tag}',
               'body': body,
               'prerelease': prerelease,
+              'target_commitish': '${COMMIT_SHA}',
           }))
           ")