git-artifacts: also build the nuget package

The two NuGet artifact exists only in the 64-bit version. So let's make
them in a separate, non-matrix job.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

.github/workflows/git-artifacts.yml

@@ -327,3 +327,52 @@ jobs:
         with:
           name: ${{matrix.artifact.name}}-${{matrix.arch.name}}
           path: artifacts
+  nuget:
+    runs-on: windows-latest
+    needs: pkg
+    steps:
+      - name: Download pkg-x86_64
+        uses: actions/download-artifact@v1
+        with:
+          name: pkg-x86_64
+          path: pkg-x86_64
+      - name: Download bundle-artifacts
+        uses: actions/download-artifact@v1
+        with:
+          name: bundle-artifacts
+          path: bundle-artifacts
+      - name: Download git-sdk-64-build-installers
+        shell: bash
+        run: |
+          # Use Git Bash to download and unpack the artifact
+
+          ## Get artifact
+          urlbase=https://dev.azure.com/git-for-windows/git/_apis/build/builds
+          id=${{ needs.pkg.outputs.latest-sdk64-extra-build-id }}
+          download_url=$(curl "$urlbase/$id/artifacts" |
+            jq -r '.value[] | select(.name == "git-sdk-64-build-installers").resource.downloadUrl')
+
+          curl -o artifacts.zip "$download_url"
+
+          ## Unpack artifact
+          unzip artifacts.zip
+      - name: Clone and update build-extra
+        shell: bash
+        run: |
+          d=git-sdk-64-build-installers/usr/src/build-extra &&
+          git clone --single-branch -b main https://github.com/git-for-windows/build-extra $d &&
+          git -C $d pull "$PWD"/bundle-artifacts/build-extra.bundle main
+      - uses: nuget/setup-nuget@v1
+      - name: Build 64-bit NuGet packages
+        shell: powershell
+        run: |
+          & .\git-sdk-64-build-installers\usr\bin\bash.exe -lc @"
+            /usr/src/build-extra/please.sh make_installers_from_mingw_w64_git --version=`$(cat pkg-x86_64/ver) -o artifacts --nuget --pkg=pkg-x86_64/mingw-w64-x86_64-git-[0-9]*.tar.xz --pkg=pkg-x86_64/mingw-w64-x86_64-git-doc-html-[0-9]*.tar.xz &&
+            /usr/src/build-extra/please.sh make_installers_from_mingw_w64_git --version=`$(cat pkg-x86_64/ver) -o artifacts --nuget-mingit &&
+            openssl dgst -sha256 artifacts/Git*.nupkg | sed \"s/.* //\" >artifacts/sha-256.txt
+          "@
+      - name: Publish nuget-x86_64
+        uses: actions/upload-artifact@v1
+        with:
+          name: nuget-x86_64
+          path: artifacts