chore: signing release artifacts (#175)

Author: marianogoldman

.github/workflows/release.yml

@@ -23,5 +23,7 @@ jobs:
             - name: Publish to the Maven Central Repository
               run: gradle publish
               env:
+                  ORG_GRADLE_PROJECT_signingKey: ${{ secrets.GPG_SIGNING_KEY }}
+                  ORG_GRADLE_PROJECT_signingPassword: ${{ secrets.GPG_SIGNING_PASSWORD }}
                   MAVEN_USERNAME: ${{ secrets.OSSRH_USERNAME }}
                   MAVEN_PASSWORD: ${{ secrets.OSSRH_TOKEN }}

build.gradle

@@ -150,9 +150,9 @@ publishing {
     }
 }
 
-if (project.hasProperty("signing.keyId")) {
-    apply plugin: 'signing'
-    signing {
-        sign publishing.publications.mavenJava
-    }
+signing {
+    def signingKey = findProperty("signingKey")
+    def signingPassword = findProperty("signingPassword")
+    useInMemoryPgpKeys(signingKey as String, signingPassword as String)
+    sign publishing.publications.mavenJava
 }