CI: try to not fail if ucrt fails

.github/workflows/main.yml

@@ -11,9 +11,9 @@ jobs:
       fail-fast: false
       matrix:
         include: [
-          { msystem: MINGW64, arch: x86_64 },
-          { msystem: MINGW32, arch: i686   },
-          { msystem: UCRT64, arch: ucrt-x86_64 }
+          { msystem: MINGW64, arch: x86_64, can-fail: false },
+          { msystem: MINGW32, arch: i686, can-fail: false },
+          { msystem: UCRT64, arch: ucrt-x86_64, can-fail: true }
         ]
     steps:
 
@@ -49,12 +49,14 @@ jobs:
 
       - name: CI-Build
         shell: msys2 {0}
+        continue-on-error: ${{ matrix.can-fail }}
         run: |
           cd /C/_
           MINGW_INSTALLS=${{ matrix.msystem }} ./.ci/ci-build.sh
 
       - name: "Upload binaries"
         uses: actions/upload-artifact@v2
+        continue-on-error: ${{ matrix.can-fail }}
         with:
           name: ${{ matrix.msystem }}-packages
           path: C:/_/artifacts/*.pkg.tar.*