chore(CI): move windows build to separate workflow (#5405)

* chore(CI): move windows build to separate workflow

* chore(README): add status badge

.github/workflows/windows_build.yml

@@ -0,0 +1,35 @@
+name: windows-build
+on:
+  push:
+    branches:
+      - '**'         # matches every branch
+      - '!coverity_scan'   # excludes coverity_scan
+  pull_request:
+
+jobs:
+  windows-build:
+    strategy:
+      fail-fast: false
+    runs-on: windows-2019
+    name: windows-2019-MSVC16
+    if: github.repository == 'azerothcore/azerothcore-wotlk'
+    steps:
+      - uses: actions/checkout@v2
+      - name: Configure OS
+        run: choco install --no-progress openssl
+      - name: Build
+        shell: bash
+        run: |
+          mkdir -p build && cd build
+          cmake .. -DTOOLS=ON
+          cmake --build . --config Release --parallel 4
+      - name: Copy dll files
+        shell: bash
+        run: |
+          cp "/c/mysql-5.7.21-winx64/lib/libmysql.dll" "build/bin/Release/"
+          cp "/c/Program Files/OpenSSL-Win64/bin/libcrypto-1_1-x64.dll" "build/bin/Release/"
+          cp "/c/Program Files/OpenSSL-Win64/bin/libssl-1_1-x64.dll" "build/bin/Release/"
+      - uses: actions/upload-artifact@v2
+        with:
+          name: windows-2019-MSVC16-release
+          path: build/bin/Release