Remove function inspection in tests

Let's not use inspect and try to be overly smart about it. Since we're
only testing one in the meantime, it maybe better to just list down all
the rules aliases we'll have.

Signed-off-by: Lester James V. Miranda <ljvmiranda@gmail.com>

tests/test_rules.py

@@ -1,7 +1,6 @@
 # -*- coding: utf-8 -*-
 
 # Import standard library
-from inspect import getmembers, isfunction
 from typing import Tuple, List
 
 # Import modules
@@ -13,11 +12,9 @@
 from seagull import lifeforms as lf
 from seagull.rules import conway_classic
 
-all_rules = [
-    fn
-    for name, fn in getmembers(sg.rules, predicate=isfunction)
-    if (not name.startswith("_") & ("life_rule" in name))  # ignore private
-]
+
+# Define all rules here
+all_rules = [("conway_classic", sg.rules.conway_classic)]
 
 
 @pytest.mark.parametrize("rule_name, fn", all_rules)