Update build.yml

.github/workflows/build.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Set executable permissions
         run: chmod +x build.sh
@@ -21,3 +21,11 @@ jobs:
           -v "${{ github.workspace }}/files:/home/build/immortalwrt/files" \
           -v "${{ github.workspace }}/build.sh:/home/build/immortalwrt/build.sh" \
           immortalwrt/imagebuilder:x86-64-openwrt-23.05.4 /bin/sh /home/build/immortalwrt/build.sh
+
+      - name: Upload firmware
+        uses: actions/upload-artifact@v3
+        with:
+          name: firmware
+          path: |
+            ./bin/*.bin
+            ./bin/*.img.gz