Avoid logging a warning when replacing an ignored config entry (#142114)

Replacing an ignored config entry with one from the user
flow should not generate a warning. We should only warn
if we are replacing a usable config entry.

Followup to adjust the warning added in #130567
cc @epenet

homeassistant/config_entries.py

@@ -1612,7 +1612,11 @@ class ConfigEntriesFlowManager(
                 result["handler"], flow.unique_id
             )
 
-        if existing_entry is not None and flow.handler != "mobile_app":
+        if (
+            existing_entry is not None
+            and flow.handler != "mobile_app"
+            and existing_entry.source != SOURCE_IGNORE
+        ):
             # This causes the old entry to be removed and replaced, when the flow
             # should instead be aborted.
             # In case of manual flows, integrations should implement options, reauth,