ci(Windows): Build multiple projects in parallel (#215)

Author: tido64

.github/workflows/build.yml

@@ -337,11 +337,11 @@ jobs:
         working-directory: example/windows
       - name: Build
         run: |
-          MSBuild Example.sln -t:Rebuild -p:Configuration=${{ matrix.configuration }} -p:Platform=${{ matrix.platform }}
+          MSBuild Example.sln -t:Rebuild -p:Configuration=${{ matrix.configuration }} -p:Platform=${{ matrix.platform }} -m
         working-directory: example/windows
       - name: Test
         run: |
-          MSBuild ReactTestAppTests.vcxproj -t:Build -p:Configuration=${{ matrix.configuration }} -p:Platform=${{ matrix.platform }}
+          MSBuild ReactTestAppTests.vcxproj -t:Build -p:Configuration=${{ matrix.configuration }} -p:Platform=${{ matrix.platform }} -m
           if ("${{ matrix.platform }}" -eq "x64") { VSTest.Console.exe ${{ matrix.platform }}\${{ matrix.configuration }}\ReactTestAppTests.dll }
         working-directory: example/windows/ReactTestAppTests
   windows-template:
@@ -388,8 +388,8 @@ jobs:
         working-directory: template-example
       - name: Build
         run: |
-          if ("${{ matrix.template }}" -eq "all") { MSBuild windows/TemplateExample.sln -t:Rebuild -p:Platform=x64 }
-          else { MSBuild TemplateExample.sln -t:Rebuild -p:Platform=x64 }
+          if ("${{ matrix.template }}" -eq "all") { MSBuild windows/TemplateExample.sln -t:Rebuild -p:Platform=x64 -m }
+          else { MSBuild TemplateExample.sln -t:Rebuild -p:Platform=x64 -m }
         working-directory: template-example
   release:
     needs: