Use correct build step

.gitea/workflows/build.yml

@@ -0,0 +1,18 @@
+name: Gitea Actions Demo
+on: push
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Setup Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '21'
+
+      - name: Check out
+        uses: actions/checkout@v4
+
+      - name: Build
+        run: ./gradlew jar

.gitea/workflows/publish.yml

@@ -0,0 +1,29 @@
+name: Gitea Actions Demo
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - '*'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Setup Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '21'
+
+      - name: Check out
+        uses: actions/checkout@v4
+
+      - name: Build
+        run: ./gradlew jar
+
+      - name: Publish
+        run: ./gradlew publish
+        env:
+          ORG_GRADLE_PROJECT_GiteaUsername: ${{secrets.username}}
+          ORG_GRADLE_PROJECT_GiteaPassword: ${{secrets.password}}