Upgrade astroid to 2.7.3
diff --git a/setup.cfg b/setup.cfg
index e70a731..d3b352e 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -44,7 +44,7 @@
 packages = find:
 install_requires =
     platformdirs>=2.2.0
-    astroid>=2.7.2,<2.8 # (You should also upgrade requirements_test_min.txt)
+    astroid>=2.7.3,<2.8 # (You should also upgrade requirements_test_min.txt)
     isort>=4.2.5,<6
     mccabe>=0.6,<0.7
     toml>=0.7.1