CI mac/win: pkg-config installation

Author: andreasabel

.github/workflows/test-mac.yaml

@@ -46,6 +46,10 @@ jobs:
 
     # actions:
 
+    - name: Set PKG_CONFIG_PATH for the ICU library
+      run: |
+        echo PKG_CONFIG_PATH="$(brew --prefix)/opt/icu4c/lib/pkgconfig" >> "${GITHUB_ENV}"
+
     - name: ⏬ Install stack
       run: |
         mkdir -p ~/.local/bin

.github/workflows/test-windows.yaml

@@ -69,7 +69,7 @@ jobs:
 
     - name: Install the icu library
       run: |
-        ./stack exec -- pacman -S --noconfirm "mingw-w64-x86_64-icu"
+        ./stack exec -- pacman -S --noconfirm mingw-w64-x86_64-icu mingw-w64-x86_64-pkgconf
 
     - name: 📸 Build Snapshot
       run: |