cmake generation fails if PATH contains "./"

The new Gaudi cmake generation fails if $PATH contains the current directory (./):

-- Gaudi will be built using C++17 standard.
-- Using VectorClass instrset_detect 2.01.02 at /cvmfs/lhcb.cern.ch/lib/lcg/releases/vectorclass/2.01.02-cdfdb/x86_64-c
entos7-gcc9-opt
-- Configuring done
CMake Error at cmake/GaudiToolbox.cmake:1041 (file):
  Error evaluating generator expression:

    $<SHELL_PATH:$<REMOVE_DUPLICATES:$<GENEX_EVAL:$<TARGET_PROPERTY:target_runtime_paths,runtime_path>>;/cvmfs/lhcb.cer
n.ch/lib/lcg/releases/DD4hep/v01-14-4-gf4343fc-a0220/x86_64-centos7-gcc9-opt/bin;/
[...]
git/2.26.2-x86_64-centos7/bin;.;/afs/cern.ch/user/f/fwinkl/afs/bin;/afs/cern.ch/user/f/fwinkl/afs/.local/bin;/var/sbin;
/usr/sue/bin;/usr/local/bin;/usr/bin;/afs/cern.ch/user/f/fwinkl/bin;/usr/local/sbin;/usr/sbin;/afs/cern.ch/work/f/fwink
l/soft/global/bin>>

  "." is not an absolute path.
Call Stack (most recent call first):
  CMakeLists.txt:93 (include)


-- Generating done
CMake Generate step failed.  Build files cannot be regenerated correctly.