Refactor: Optimize Dockerfile structure

Combined some multiple RUN commands to reduce Docker container layers.

Moved the rm cache cleaning command after the apt-get installation command for smaller laysr size.

docker/Dockerfile

@@ -30,20 +30,13 @@ RUN if [ "$G4F_VERSION" = "" ] ; then \
   apt-get -qqy install git \
   ; fi
 
-# Python packages
+# Install Python3, pip, remove OpenJDK 11, clean up
 RUN apt-get -qqy update \
-  && apt-get -qqy install \
-    python3 \
-    python-is-python3 \
-    pip
-
-# Remove java
-RUN apt-get -qyy remove openjdk-11-jre-headless
-
-# Cleanup
-RUN rm -rf /var/lib/apt/lists/* /var/cache/apt/* \
+  && apt-get -qqy install python3 python-is-python3 pip \
+  && apt-get -qyy remove openjdk-11-jre-headless \
   && apt-get -qyy autoremove \
-  && apt-get -qyy clean
+  && apt-get -qyy clean \
+  && rm -rf /var/lib/apt/lists/* /var/cache/apt/*
 
 # Update entrypoint
 COPY docker/supervisor.conf /etc/supervisor/conf.d/selenium.conf
@@ -57,15 +50,13 @@ RUN if [ "$G4F_NO_GUI" ] ; then \
 # Change background image
 COPY docker/background.png /usr/share/images/fluxbox/ubuntu-light.png
 
-# Add user
+# Add user, fix permissions
 RUN groupadd -g $G4F_USER_ID $G4F_USER \
   && useradd -rm -G sudo -u $G4F_USER_ID -g $G4F_USER_ID $G4F_USER \
-  && echo "${G4F_USER}:${G4F_PASS}" | chpasswd
-
-# Fix permissions
-RUN mkdir "${SE_DOWNLOAD_DIR}"
-RUN chown "${G4F_USER_ID}:${G4F_USER_ID}" $SE_DOWNLOAD_DIR /var/run/supervisor /var/log/supervisor
-RUN chown "${G4F_USER_ID}:${G4F_USER_ID}" -R /opt/bin/ /usr/bin/chromedriver /opt/selenium/
+  && echo "${G4F_USER}:${G4F_PASS}" | chpasswd \
+  && mkdir "${SE_DOWNLOAD_DIR}" \
+  && chown "${G4F_USER_ID}:${G4F_USER_ID}" $SE_DOWNLOAD_DIR /var/run/supervisor /var/log/supervisor \
+  && chown "${G4F_USER_ID}:${G4F_USER_ID}" -R /opt/bin/ /usr/bin/chromedriver /opt/selenium/
 
 # Switch user
 USER $G4F_USER_ID