Fix Nightly CMake (micro-ROS#555) (micro-ROS#556)

Signed-off-by: Pablo Garrido <pablogs9@gmail.com>
(cherry picked from commit a73f847)

Co-authored-by: Pablo Garrido <pablogs9@gmail.com>

.github/workflows/nightly.yml

@@ -338,14 +338,6 @@ jobs:
           apt update
           apt upgrade -y
           # Install last version of CMake
-          apt install -y apt-transport-https ca-certificates gnupg software-properties-common wget
-          if [ $(lsb_release -sr) = "22.04" ]; then
-            echo "Using Ubuntu mainline CMake"
-          else
-            echo "Adding Kitware CMake repo to install CMake"
-            wget -O - https://apt.kitware.com/keys/kitware-archive-latest.asc 2>/dev/null | gpg --dearmor - | sudo tee /etc/apt/trusted.gpg.d/kitware.gpg >/dev/null
-            apt-add-repository 'deb https://apt.kitware.com/ubuntu/ focal main'
-          fi
           apt-get update
           apt install -y python3-colcon-metadata python3-pip cmake
           rosdep update --os=ubuntu:jammy --rosdistro $ROS_DISTRO