Fix dep specification

Author: benjeffery

setup.cfg

@@ -55,7 +55,7 @@ install_requires =
     tskit>=0.5.3
     numcodecs>=0.6
     # issues 965 and 967 at zarr-python prevent usage of 2.11.0 and 2.11.1
-    zarr>=2.2!=2.11.0!=2.11.1!=2.11.2
+    zarr>=2.2,!=2.11.0,!=2.11.1,!=2.11.2
     lmdb
     sortedcontainers
     attrs>=19.2.0