Add new test stage in CTest configuration

Installl CbmRoot and remove part of the source directory

Add code which tests if the installtion of CbmRoot works and if the installed
version is functional. Test the "make install" target and run some macros from
teh installation directory.

To be able to test the CbmRoot installation it is necessary that no header
files are accessible in the source directory since this is the fallback for
ROOT when compiling a macro. To achieve this the directories containing any
headers are removed from the source directory.
This is a dangerous operation when executed in a source directory used for
active development. The installation test should only be used when running
the CI/CD workflow.

CbmRoot_test.cmake

@@ -130,8 +130,27 @@ If(NOT _RETVAL)
     EndIf()
   EndIf()
 
+  If(EXTRA_FLAGS MATCHES "INSTALL_PREFIX" AND EXTRA_FLAGS MATCHES "CBM_TEST_INSTALL" AND NOT _ctest_test_ret_val)
+    Message("Testing Installation")
+    execute_process(COMMAND ${BUILD_COMMAND} install -j$ENV{number_of_processors} WORKING_DIRECTORY ${CTEST_BINARY_DIRECTORY}
+                    RESULTS_VARIABLE _install_ret_value
+                   )
+    if (NOT _install_ret_value)
+      execute_process(COMMAND ${CMAKE_EXECUTABLE_NAME} -E rm -R MQ algo analysis core external fles mvd reco sim
+                      WORKING_DIRECTORY ${CTEST_SOURCE_DIRECTORY}
+                     )
+      message("executing test suite in ${CTEST_BINARY_DIRECTORY}/install")
+      execute_process(COMMAND ${CTEST_SOURCE_DIRECTORY}/cmake/scripts/execute_installation_test.sh ${CTEST_BINARY_DIRECTORY}/install
+                      RESULTS_VARIABLE _install_ret_value
+                     )
+    endif()
+ Else()
+   # if installation isn't tested the return value should be 0
+   set(_install_ret_value false)
+ EndIf()
+
   # Pipeline should fail also in case of failed tests
-  if (_ctest_test_ret_val)
+  if (_ctest_test_ret_val OR _install_ret_value)
     If(${CMAKE_VERSION} VERSION_LESS 3.14.0)
     Else()
       message(STATUS " ")