no longer depends on openssl

.github/workflows/rust.yml

@@ -20,21 +20,25 @@ jobs:
 
   build:
     name: Build
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
 
     steps:
+      - name: musl-tools
+        run: |
+          sudo apt-get install musl-tools
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal
           toolchain: stable
           override: true
+          target: x86_64-unknown-linux-musl
       - uses: Swatinem/rust-cache@v1
       - uses: actions-rs/cargo@v1
         with:
           command: build
-          args: --release
+          args: --release --target x86_64-unknown-linux-musl
       - uses: actions/upload-artifact@v2
         with:
           name: dispenser
-          path: target/release/dispenser
+          path: target/x86_64-unknown-linux-musl/release/dispenser