fix alpine bash

Author: sdcb

.github/workflows/opencvsharp.yml

@@ -162,7 +162,7 @@ jobs:
             fi
 
           elif [[ "${{ matrix.os }}" =~ ^alpine ]]; then
-            EXTRA_FLAGS+=" -DCMAKE_SHARED_LINKER_FLAGS='-static-libstdc++ -static-libgcc'"
+            # EXTRA_FLAGS="${EXTRA_FLAGS} -DCMAKE_SHARED_LINKER_FLAGS='-static-libstdc++ -static-libgcc'"
 
           elif [[ ${{ matrix.os }} == "android" ]]; then
             OpenCV_DIR="${{ github.workspace }}/opencv/sdk/native/jni"