Check for readline module instead of Windows when initializing autocomplete in install (#1104)

tests/test_install.py

@@ -0,0 +1,13 @@
+from unittest import mock
+import pytest
+import sys
+
+
+@pytest.mark.filterwarnings(
+    "ignore:.*imp module is deprecated.*"
+)  # ansiwrap spits out an unrelated warning
+def test_initialize_autocomplete_runs_without_readline():
+    from jrnl import install
+
+    with mock.patch.dict(sys.modules, {"readline": None}):
+        install._initialize_autocomplete()  # should not throw exception