Fix mismatch in env and from mime header when signing mail

data/conf/rspamd/local.d/dkim_signing.conf

@@ -1,7 +1,7 @@
 # If false, messages with empty envelope from are not signed
 allow_envfrom_empty = false;
 # If true, envelope/header domain mismatch is ignored
-allow_hdrfrom_mismatch = true;
+allow_hdrfrom_mismatch = false;
 # If true, multiple from headers are allowed (but only first is used)
 allow_hdrfrom_multiple = true;
 # If true, username does not need to contain matching domain