Adds the note: acme.domains is a startup configuration

Author: geraldcroes

docs/configuration/acme.md

@@ -144,6 +144,7 @@ entryPoint = "https"
 
 # Domains list.
 # Only domains defined here can generate wildcard certificates.
+# The certificates for these domains are negotiated at traefik startup only.
 #
 # [[acme.domains]]
 #   main = "local1.com"
@@ -302,6 +303,9 @@ You can provide SANs (alternative domains) to each main domain.
 All domains must have A/AAAA records pointing to Traefik.
 Each domain & SAN will lead to a certificate request.
 
+!!! note
+    The certificates for the domains listed in `acme.domains` are negotiated at traefik startup only.
+
 ```toml
 [acme]
 # ...