add pyfzf_iter install to tox

my/core/denylist.py

@@ -103,6 +103,8 @@ having to mix data filtering logic with parsing/loading/caching (the stuff HPI d
 """
 
 # https://github.com/seanbreckenridge/pyfzf
+# TODO: add pip install instructions for this to docs, cant use REQUIRES because
+# this a core module and not discovered to be installed with `hpi module install`
 REQUIRES = ["pyfzf_iter"]
 
 import json

tox.ini

@@ -44,6 +44,9 @@ commands =
     pip install cachew
     pip install orjson
 
+    # for my.core.denylist
+    pip install pyfzf_iter
+
     hpi module install my.location.google
     pip install ijson # optional dependency