add specific paths

Author: cvanelteren

.github/workflows/build.yml

@@ -72,9 +72,10 @@ jobs:
           CIBW_BEFORE_BUILD: >
             python -c "import utils; utils.GeosLibrary('${{ env.GEO_VERSION }}').build('extern', njobs=16)"
           CIBW_ENVIRONMENT: >
-            GEOS_DIR=/project/extern
-            CFLAGS="-I/project/extern/include"
-            LDFLAGS="-L/project/extern/lib"
+            GEOS_DIR=${{ github.workspace }}${{ runner.os == 'Windows' && '\\extern' || '/extern' }}
+            CFLAGS=-I${{ github.workspace }}${{ runner.os == 'Windows' && '\\extern\\include' || '/extern/include' }}
+            LDFLAGS=-L${{ github.workspace }}${{ runner.os == 'Windows' && '\\extern\\lib' || '/extern/lib' }}
+                    GEOS_DIR=/project/extern
           CIBW_TEST_COMMAND: >
             cd {project}
             pip install pytest