Merge pull request #154 from stac-utils/dependabot/pip/dot-github/workflows/virtualenv-20.16.6

Bump virtualenv from 20.16.5 to 20.16.6 in /.github/workflows

Author: Phil Varner

.github/workflows/constraints.txt

@@ -2,4 +2,4 @@ pip==22.3
 nox==2022.8.7
 nox-poetry==1.0.1
 poetry~=1.2.2
-virtualenv==20.16.5
+virtualenv==20.16.6