Add `gnupg` to Dockerfile-cpu
diff --git a/utils/docker/Dockerfile-cpu b/utils/docker/Dockerfile-cpu
index d6fac645dba..f3f81ec02c2 100644
--- a/utils/docker/Dockerfile-cpu
+++ b/utils/docker/Dockerfile-cpu
@@ -11,7 +11,7 @@ ADD https://ultralytics.com/assets/Arial.ttf https://ultralytics.com/assets/Aria
 # Install linux packages
 RUN apt update
 RUN DEBIAN_FRONTEND=noninteractive TZ=Etc/UTC apt install -y tzdata
-RUN apt install --no-install-recommends -y python3-pip git zip curl htop libgl1-mesa-glx libglib2.0-0 libpython3-dev
+RUN apt install --no-install-recommends -y python3-pip git zip curl htop libgl1-mesa-glx libglib2.0-0 libpython3-dev gnupg
 # RUN alias python=python3
 
 # Install pip packages

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

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## 🛠️ PR Summary

<sub>Made with ❤️ by [Ultralytics Actions](https://github.com/ultralytics/actions)<sub>

### 🌟 Summary
Update to YOLOv5's CPU Dockerfile to include `gnupg` package.

### 📊 Key Changes
- Addition of the `gnupg` package to the Dockerfile used for CPU-based installations.

### 🎯 Purpose & Impact
- **Purpose**: The `gnupg` package is used for encryption and signing data and communications. Its inclusion in the Dockerfile indicates a need for security features that can enforce authenticity or confidentiality in certain operations within the YOLOv5 environment.
- **Impact**: Users leveraging the Docker container for YOLOv5 on CPU systems will now have additional cryptographic capabilities, allowing for enhanced security measures when needed. This change might be in preparation for future features that require secure data transactions or verification of data integrity.