Problem while building for Ubuntu 18.04

[alice1321]

Hello,

I'm trying to compile the library on Ubuntu 18.04, however I'm encountering some issues as I will report in the following:

CMake Error at /opt/ros/melodic/share/catkin/cmake/catkinConfig.cmake:83 (find_package):
  Could not find a package configuration file provided by "gazebo" with
  any of the following names:

    gazeboConfig.cmake
    gazebo-config.cmake

  Add the installation prefix of "gazebo" to CMAKE_PREFIX_PATH or set
  "gazebo_DIR" to a directory containing one of the above files.  If
  "gazebo" provides a separate development package or SDK, be sure it has
  been installed.

I'm trying to compile using the following procedure:

1. Create catkin_ws/src
2. Clone the repository in the src directory
3. catkin_make

I've already tried setting the CMAKE_PREFIX_PATH and the gazebo_DIR however none of this solutions worked.
I've also installed libgazebo-dev as suggested in ros-simulation/gazebo_ros_pkgs#813 but it doesn't solve the problem either.
I've tried using different gazebo versions but the same error presents both in gazebo 9 and gazebo 11.
I mention that the configuration file is in the system as

$ dpkg -L libgazebo11-dev | grep gazebo-config.cmake
> /usr/lib/x86_64-linux-gnu/cmake/gazebo/gazebo-config.cmake

Thank you!