Adding conda-remove-defaults: true to conda CI options.

[vitenti]

Description

Adding conda-remove-defaults: true to conda CI options.
This assures that the defaults conda channel will not be used.

Checklist:

The following checklist will make sure that you are following the code style and
guidelines of the project as described in the
contributing page.

• I have run bash pre-commit-check and fixed any issues
• I have added tests that prove my fix is effective or that my feature works
• I have made corresponding changes to the documentation
• I have 100% test coverage for my changes (please check this after the CI system has verified the coverage)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.9%. Comparing base (bd8ce57) to head (727ed3a).
Report is 1 commits behind head on master.

Additional details and impacted files

@@          Coverage Diff           @@
##           master    #476   +/-   ##
======================================
  Coverage    99.9%   99.9%           
======================================
  Files          54      54           
  Lines        4163    4163           
======================================
  Hits         4160    4160           
  Misses          3       3