Drop duplicate apt-get updates

Author: Chuxel

containers/cpp/.devcontainer/Dockerfile

@@ -10,13 +10,12 @@ ENV DEBIAN_FRONTEND=noninteractive
 # Set the default shell to bash rather than sh
 ENV SHELL /bin/bash
 
+# Configure apt and install packages
 RUN apt-get update \
-    #
-    # Configure apt
     && apt-get -y install --no-install-recommends apt-utils 2>&1 \
     # 
     # Verify git, process tools, lsb-release (useful for CLI installs) installed
-    && apt-get update && apt-get -y install git procps lsb-release \
+    && apt-get -y install git procps lsb-release \
     #
     # Install C++ tools
     && apt-get -y install build-essential cmake cppcheck valgrind \

containers/markdown/.devcontainer/Dockerfile

@@ -10,7 +10,6 @@ ENV DEBIAN_FRONTEND=noninteractive
 # Set the default shell to bash rather than sh
 ENV SHELL /bin/bash
 
-
 # Configure apt and install packages
 RUN apt-get update \
     #

containers/ruby-2/.devcontainer/Dockerfile

@@ -14,7 +14,7 @@ ENV SHELL /bin/bash
 RUN apt-get update \
     && apt-get -y install --no-install-recommends apt-utils 2>&1 \
     # Verify git, process tools installed
-    && apt-get update && apt-get -y install git procps lsb-release \
+    && apt-get -y install git procps lsb-release \
     #
     # Install ruby-debug-ide and debase
     && gem install ruby-debug-ide \