fix: remove kaniko incompatible instruction

Dockerfile

@@ -4,7 +4,7 @@ RUN apt-get update \
         xz-utils \
     && rm -rf /var/lib/apt/lists/*
 ADD https://storage.googleapis.com/flutter_infra_release/releases/stable/linux/flutter_linux_3.24.4-stable.tar.xz /flutter.tar.xz
-RUN tar -C /opt/ -xJf /flutter.tar.xz
+RUN tar -C /opt/ --exclude=cache -xJf /flutter.tar.xz
 
 FROM docker.io/debian:12-slim
 RUN useradd -m app
@@ -20,7 +20,7 @@ RUN sdkmanager \
         "cmdline-tools;9.0" \
         "platform-tools;35.0.2" \
         "platforms;android-35"
-COPY --from=build --chown=app:app --exclude=cache /opt/ /opt/
+COPY --from=build --chown=app:app /opt/ /opt/
 USER app
 ENV PATH="/opt/flutter/bin:$PATH"
 RUN flutter doctor