Conda: mcviewtest / mxviewtest add dependency for jinja2

[willend]

In conda environments, the mcviewtest tool may not function out of the box:

mcviewtest $PWD
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
	LANGUAGE = (unset),
	LC_ALL = (unset),
	LC_CTYPE = "UTF-8",
	LANG = "C"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
Traceback (most recent call last):
  File "/usr/share/mcstas/tools/Python/mctest/mcviewtest.py", line 12, in <module>
    import jinja2
ModuleNotFoundError: No module named 'jinja2'

To fix, simply conda install jinja2