Upgrade warnings to errors when testing

ConorMacBride · ConorMacBride · commit 35422474b726 · 2022-10-25T23:27:53.000+01:00
diff --git a/setup.cfg b/setup.cfg
@@ -50,6 +50,8 @@ testpaths = tests
 xfail_strict = true
 markers =
     array_compare: for functions using array comparison
+filterwarnings =
+    error
 
 [flake8]
 max-line-length = 150
