Add missing find_package statement for pytools to PyUtils package

The `PyUtils` package makes use of `pytools`, but the package
`CMakeLists.txt` file does not explicitly call `find_package( pytools )`.
Instead it relies on the calls in `DataQuality/DQDefects` and
`DataQuality/DQUtils`, so currently all projects which don't include
either of these packages are broken in `master`. This should fix
ATEAM-427.


Former-commit-id: 9f69907d

Tools/PyUtils/CMakeLists.txt

@@ -12,6 +12,7 @@ atlas_depends_on_subdirs( PUBLIC
 
 # External dependencies:
 find_package( PythonLibs )
+find_package( pytools )
 find_package( ROOT COMPONENTS Core PyROOT Tree MathCore Hist RIO pthread )
 
 # Install files from the package: