Update Binder's core Conda to fix libicui18n.so.56 issue?

[Rich Signell]

Our repo that used to work find on Binder:
https://github.com/ioos/notebooks_demos
now has a library incompatibility issue that indicates that Binder's core conda needs to be update.

binder-project/binder#86

---> 20 from lxml import etree
     21 from owslib import fes
     22 from owslib.ows import ExceptionReport

ImportError: libicui18n.so.56: cannot open shared object file: No such file or directory

[Jean-Luc Stevens]

Just to say that I encountered an identical sounding issue on one of my projects and fixed it by pinning the lxml version:

- lxml==3.6.0

Maybe that will help you too!

[Phillip J. Wolfram]

This helped me, thank you @jlstevens!