update classnames version to 2.2.6

[kittle31]

a fix for this error:
JedWatson/classnames#106
was added in classnames v 2.2.6.

update dependency version from 2.2.5 to 2.2.6

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[codecov-io]

Codecov Report

Merging #702 into rc0.11.0 will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           rc0.11.0     #702   +/-   ##
=========================================
  Coverage     94.98%   94.98%           
=========================================
  Files            73       73           
  Lines          2912     2912           
  Branches        444      444           
=========================================
  Hits           2766     2766           
  Misses           50       50           
  Partials         96       96

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[kittle31]

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project (if not, look below for help). Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

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I signed it

[moog16]

fixes #703