ci: Use correct signing secret name (#62)

The secret name is `SIGNING_KEY_ID` and not `SIGNING_KEY`.

Author: matrei

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
           ORG_GRADLE_PROJECT_sonatypeUsername: ${{ secrets.SONATYPE_USERNAME }}
           ORG_GRADLE_PROJECT_sonatypePassword: ${{ secrets.SONATYPE_PASSWORD }}
           ORG_GRADLE_PROJECT_sonatypeStagingProfileId: ${{ secrets.SONATYPE_STAGING_PROFILE_ID }}
-          SIGNING_KEY: ${{ secrets.SIGNING_KEY }}
+          SIGNING_KEY: ${{ secrets.SIGNING_KEY_ID }}
           SIGNING_PASSPHRASE: ${{ secrets.SIGNING_PASSPHRASE }}
         run: >
           ./gradlew