TEST: turning off 3.6 on github actions

[sjsrey]

3.6 job grabs an older version of geopandas which is causing the voronoi tests to fail (those pass on 3.6 on travis).

[AppVeyorBot]

✅ Build libpysal 1.0.57 completed (commit e9f4b95c03 by @sjsrey)

[codecov]

Codecov Report

Merging #266 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #266   +/-   ##
=======================================
  Coverage   81.02%   81.02%           
=======================================
  Files         116      116           
  Lines       11574    11574           
=======================================
  Hits         9378     9378           
  Misses       2196     2196           

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[AppVeyorBot]

✅ Build libpysal 1.0.60 completed (commit a1bef93b98 by @sjsrey)

[jGaboardi]

FWI, I have the working on a complete solution with GitHub Actions in spaghetti and it seems like success is just around the corner.

Complete solution (pysal/spaghetti/pull/452):

• tests ubuntu, mac, windows
• tests Python 3.6, 3.7, 3.8
• tests both hard and optional requirements
• tests with both the current libpysal release and the current master
• performs code-cov
• run nightly tests

Once this is fully worked out, spaghetti will be able to migrate off of Travis and Appveyor.

[sjsrey]

will be handled in #267