Build devel manifest with access to crates.io

There's no point in keeping cargo-sources.json up to date just to keep
Devel builds going; regular CI builds also have network access.

flatpak/de.swsnr.turnon.Devel.yaml

@@ -20,16 +20,16 @@ modules:
   - name: turnon
     buildsystem: simple
     sources:
-      - cargo-sources.json
       - type: dir
         path: ".."
+    build-options:
+      build-args:
+        - --share=network
     build-commands:
-      # Point cargo to vendored sources downloaded by flatpak builder
-      - install -Dm0644 cargo/config .cargo/config.toml
       # Patch for devel version
       - make devel
       # Build optimized binary
-      - cargo build --frozen --release --verbose
+      - cargo build --locked --release --verbose
       # Install locales
       - make LOCALEDIR=/app/share/locale/ APPID=de.swsnr.turnon.Devel install-locale
       # Install binary, app icon, desktop file, appstream metadata, DBus service, and search provider