fix: release to the Gitea API on its public URL (#997)

goreleaser's gitea_urls.api still pointed at the AWS in-cluster service (gitea-http.gitea.svc.cluster.local), which does not resolve from the Frostmoln runner. Use https://git.unbound.se/api/v1. Also drop RELEASE_TOKEN_FILE=/runner-secrets/release-token (the AWS runner mount); the Frostmoln runner exports RELEASE_TOKEN_FILE itself.

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https://claude.ai/code/session_01Ma8eHhW59hLAJuLzBnLvUu
Reviewed-on: #997

.gitea/workflows/goreleaser.yaml

@@ -5,9 +5,6 @@ on:
     tags:
       - 'v*'
 
-env:
-  RELEASE_TOKEN_FILE: /runner-secrets/release-token
-
 jobs:
   release:
     runs-on: ubuntu-latest
@@ -30,4 +27,5 @@ jobs:
         run: |
           GITEA_TOKEN=$(cat "${RELEASE_TOKEN_FILE}")
           export GITEA_TOKEN
-          goreleaser release --clean
+          # Without GOCACHEPROG: parallel builds contend for gobuildcache's locks.
+          env -u GOCACHEPROG goreleaser release --clean