add missing comma

Author: aloctavodia

R/methods.R

@@ -1820,7 +1820,7 @@ suggest_size.vsel <- function(
     if (object$nterms_max != object$nterms_all && warnings) {
       warning("Could not suggest submodel size within the searched range. ",
               "Investigate plot.vsel() to identify if the search was ",
-              "terminated too early or the criterion is too strict."
+              "terminated too early or the criterion is too strict.",
               "If this is the case, run variable selection with ",
               "larger value for `nterms_max` or use less strict criterion.")
     }