Block broken version of pytest-cov

Recently, version 6.2.0 of pytest-cov was released with support for
new pluggy hookwrappers, which require pluggy>=1.2 and pytest>=6.2.5,
but the dependency metadata wasn't updated to reflect these
requirements. There was an immediate followup release, pytest-cov 6.2.1,
that fixed the metadata problem, but that still leaves version 6.2.0 as
one that pip thinks should be safe to use with pytest<6.2.5, even though
it actually isn't. (Perhaps 6.2.0 should be yanked to deal with this,
but it looks like it probably won't be.)

Since some of our tests run with pytest 6.2.4, we were getting failures
because of this mismatch. Accordingly, in this commit I'm manually
blocking pytest-cov 6.2.0 to avoid the failure.

Author: diazona

tox.ini

@@ -24,7 +24,7 @@ deps =
     # bounds.
     pytest >=4.6, <9; python_version<'3.10'
     pytest >=6.2.4, <9; python_version>='3.10'
-    pytest-cov
+    pytest-cov !=6.2.0
     requests
 extras =
     smtp: smtp