Optimize Dockerfile to reduce image size and improve build efficiency

- Merge apt-related RUN commands in builder and final stages
- Remove redundant apt-get clean (automatically handled by base image)
- Consolidate cleanup operations within the same layer for effective
  size reduction

Reference:
- https://docs.docker.com/build/building/best-practices/#apt-get

application/Dockerfile

@@ -4,14 +4,11 @@ FROM ubuntu:24.04 as builder
 ENV DEBIAN_FRONTEND=noninteractive
 
 RUN apt-get update && \
-    apt-get install -y software-properties-common
+    apt-get install -y software-properties-common && \
-
+    add-apt-repository ppa:deadsnakes/ppa && \
-RUN add-apt-repository ppa:deadsnakes/ppa
-
 # Install necessary packages and Python
-RUN apt-get update && \
+    apt-get update && \
     apt-get install -y --no-install-recommends gcc wget unzip libc6-dev python3.11 python3.11-distutils python3.11-venv && \
-    apt-get clean && \
     rm -rf /var/lib/apt/lists/* 
 
 # Verify Python installation and setup symlink
@@ -50,12 +47,10 @@ RUN pip install --no-cache-dir --upgrade pip && \
 FROM ubuntu:24.04 as final
 
 RUN apt-get update && \
-    apt-get install -y software-properties-common
+    apt-get install -y software-properties-common && \
-
+    add-apt-repository ppa:deadsnakes/ppa && \
-RUN add-apt-repository ppa:deadsnakes/ppa
-
 # Install Python
-RUN apt-get update && apt-get install -y --no-install-recommends python3.11 && \
+    apt-get update && apt-get install -y --no-install-recommends python3.11 && \
     ln -s /usr/bin/python3.11 /usr/bin/python && \
     rm -rf /var/lib/apt/lists/*