fix(moderation): fixed unboundlocalerror

moderation/moderation.py

@@ -1736,6 +1736,8 @@ class Moderation(commands.Cog):
                         resolved_by = '?'
                     if resolved_reason is None:
                         resolved_reason = 'Could not get resolve reason during moderation import.'
+                    if resolve_timestamp is None:
+                        resolve_timestamp = timestamp
                     changes = [
                         {
                         'type': "ORIGINAL",