Try fix apprise install

Dockerfile.client

@@ -6,8 +6,7 @@ COPY . .
 RUN cargo build --bin ipmon --release
 
 FROM debian:bullseye-slim
-RUN apt update && apt -y install ca-certificates && rm -rf /var/lib/apt/lists/*
-RUN apt install python3-pip
+RUN apt update && apt -y install ca-certificates python3-pip && rm -rf /var/lib/apt/lists/*
 RUN pip install apprise -y
 WORKDIR /app
 COPY --from=build /ipmon/target/release/ipmon ./