python3Packages.blis: 0.9.1 -> 0.7.9

The blis 0.9.x packages cause segmentation faults:

explosion/thinc#771 (comment)

For this reason, Thinc/spaCy (the only users of this package in
nixpkgs) have reverted to 0.7.x until this issue is resolved.

pkgs/development/python-modules/blis/default.nix

@@ -10,14 +10,16 @@
 
 buildPythonPackage rec {
   pname = "blis";
-  version = "0.9.1";
+  # Do not update to BLIS 0.9.x until the following issue is resolved:
+  # https://github.com/explosion/thinc/issues/771#issuecomment-1255825935
+  version = "0.7.9";
   format = "setuptools";
 
   disabled = pythonOlder "3.7";
 
   src = fetchPypi {
     inherit pname version;
-    hash = "sha256-fOrEZoAfnZfss04Q3e2MJM9eCSfqfoNNocydLtP8Nm8=";
+    hash = "sha256-Ke9MJQB3hakP/C8Ks9O9O3XNLXhWqaSCt9DayNURoJ0=";
   };
 
   postPatch = ''