Add missing spaces

data/conf/dovecot/dovecot.conf

@@ -28,7 +28,7 @@ mail_attachment_min_size = 128k
 # you do not manually modify the files in the `cur` directories in
 # mailcowdockerized_vmail-vol-1.
 # https://mailcow.github.io/mailcow-dockerized-docs/u_e-dovecot-perf/
-maildir_very_dirty_syncs=yes
+maildir_very_dirty_syncs = yes
 
 # Dovecot 2.2
 #ssl_protocols = !SSLv3