Fixes #22 Gradle Cannot Sign Binaries with ASCII Armored GPG Key

* Move environment variable to Gradle file

* Revert build type to publication

.github/workflows/publish-library.yml

@@ -10,25 +10,29 @@ jobs:
     steps:
     - name: Clone Repository
       uses: actions/checkout@v3
-      
+
     - name: Set up JDK 11
       uses: actions/setup-java@v3
       with:
         java-version: '11'
         distribution: 'temurin'
         cache: gradle
-
+
+    - name: Write Out GPG Key
+      run: |
+        echo GPG_SIGNING_KEY=$GPG_SIGNING_KEY >> gradle.properties
+        echo GPG_SIGNING_KEY_PASSWORD=$GPG_SIGNING_KEY_PASSWORD >> gradle.properties
+      env:
+        GPG_SIGNING_KEY: ${{ secrets.GPG_SIGNING_KEY }}
+        GPG_SIGNING_KEY_PASSWORD: ${{ secrets.GPG_SIGNING_KEY_PASSWORD }}
+
     - name: Publish the Library
       uses: gradle/gradle-build-action@v2
       with:
         arguments: |
           publishMultimodalSpannerPublicationToCentralRepository
-          -PcentralUsername="$CENTRAL_REPOSITORY_USERNAME"
-          -PcentralPassword="$CENTRAL_REPOSITORY_PASSWORD"
-          -PsigningKey="$GPG_SIGNING_KEY"
-          -PsigningPassword="$GPG_SIGNING_KEY_PASSWORD"
+          -PcentralUsername=$CENTRAL_REPOSITORY_USERNAME
+          -PcentralPassword=$CENTRAL_REPOSITORY_PASSWORD
       env:
         CENTRAL_REPOSITORY_USERNAME: ${{ secrets.CENTRAL_REPOSITORY_USERNAME }}
         CENTRAL_REPOSITORY_PASSWORD: ${{ secrets.CENTRAL_REPOSITORY_PASSWORD }}
-        GPG_SIGNING_KEY: ${{ secrets.GPG_SIGNING_KEY }}
-        GPG_SIGNING_KEY_PASSWORD: ${{ secrets.GPG_SIGNING_KEY_PASSWORD }}

multimodal/build.gradle.kts

@@ -143,9 +143,9 @@ publishing {
 }
 
 signing {
-    val signingKey: String? by project
-    val signingPassword: String? by project
-    useInMemoryPgpKeys(signingKey, signingPassword)
+    val GPG_SIGNING_KEY: String? by project
+    val GPG_SIGNING_KEY_PASSWORD: String? by project
+    useInMemoryPgpKeys(GPG_SIGNING_KEY, GPG_SIGNING_KEY_PASSWORD)
     sign(publishing.publications[CentralRepository.LIBRARY_NAME])
 }