fix typo and writing improvement

Also explicitly disable making users auto watch repos after their first
commit to it.

config/hosts/git/forgejo.nix

@@ -45,6 +45,9 @@
         DEFAULT_USER_VISIBILITY = "limited";
         DEFAULT_KEEP_EMAIL_PRIVATE = true;
         ENABLE_BASIC_AUTHENTICATION = false;
+        ENABLE_NOTIFY_MAIL = true;
+        AUTO_WATCH_NEW_REPOS = false;
+        AUTO_WATCH_ON_CHANGES = false;
       };
       repo = {
         DEFAULT_REPO_UNITS = "repo.code,repo.issues,repo.pulls";