Compress release assets before uploading them to Github

With debug symbols enabled, the built executables can get quite large,
so we want to compress them to save some disk space and network bandwidth.

Also, change the asset naming convention to include the arch name.

Author: malor

.github/workflows/release.yml

@@ -74,13 +74,20 @@ jobs:
           args: --release
 
       - run: |
+          rustc --print cfg | grep = > rustc.vars
+          source rustc.vars
+
+          pushd target/release
           if [ "$RUNNER_OS" == "Windows" ]; then
-            echo "ASSET_NAME=xsnippet-api-${{ matrix.os }}.exe" >> $GITHUB_ENV
-            echo "ASSET_PATH=./target/release/xsnippet-api.exe" >> $GITHUB_ENV
+            echo "ASSET_NAME=xsnippet-api-${target_arch}-${target_os}.exe.7z" >> $GITHUB_ENV
+            echo "ASSET_PATH=./target/release/xsnippet-api.exe.7z" >> $GITHUB_ENV
+            7z a xsnippet-api.exe.7z xsnippet-api.exe
           else
-            echo "ASSET_NAME=xsnippet-api-${{ matrix.os }}" >> $GITHUB_ENV
-            echo "ASSET_PATH=./target/release/xsnippet-api" >> $GITHUB_ENV
+            echo "ASSET_NAME=xsnippet-api-${target_arch}-${target_os}.gz" >> $GITHUB_ENV
+            echo "ASSET_PATH=./target/release/xsnippet-api.gz" >> $GITHUB_ENV
+            tar cvzf xsnippet-api.gz xsnippet-api
           fi
+          popd
 
       - uses: actions/upload-release-asset@v1
         env: