avoid using the libxml2 from the system library

software/erp5-util-testing/instance.cfg

@@ -40,7 +40,7 @@ environment = environment
 CPPFLAGS = -I${python2.7:location}/include/python2.7 -I${libxml2:location}/include -I${libxslt:location}/include
 LDFLAGS = -L${python2.7:location}/lib -L${libxml2:location}/lib -L${libxslt:location}/lib -L${zlib:location}/lib
 PYTHONPATH = ${python-setuptools:location}
-LD_LIBRARY_PATH = ${libxslt:location}/lib
+LD_LIBRARY_PATH = ${libxslt:location}/lib:${libxml2:location}/lib:${zlib:location}/lib
 
 [sh-environment]
 # Section exposes testing default environment as sh file. It is thus easy