neomutt: fix smtp_pass option

Configuration option `smtp_pass` is expected to evaluate a shell
command, thus its value has to be in double-quotes.

modules/programs/neomutt.nix

@@ -116,7 +116,7 @@ let
           "${smtpProto}://${escape userName}@${smtp.host}${smtpPort}";
       in {
         smtp_url = "'${smtpBaseUrl}'";
-        smtp_pass = "'`${passCmd}`'";
+        smtp_pass = ''"`${passCmd}`"'';
       };
 
   genMaildirAccountConfig = account:

tests/modules/programs/neomutt/hm-example.com-expected

@@ -10,7 +10,7 @@ set mbox_type = Maildir
 set sort = "threads"
 
 # MTA section
-set smtp_pass='`password-command`'
+set smtp_pass="`password-command`"
 set smtp_url='smtps://home.manager@smtp.example.com'