try not specify toolset with arm64

Author: sdcb

.github/workflows/opencv.yml

@@ -73,7 +73,7 @@ jobs:
         fetch-depth: 1
 
     - name: MSVC Environment(Windows Only)
-      if: startsWith(matrix.os, 'win') && matrix.arch == 'x64'
+      if: startsWith(matrix.os, 'win')
       uses: ilammy/msvc-dev-cmd@v1
       with:
         arch: ${{ matrix.arch }}