patch 8.2.0268: trycatch test fails

Problem:    Trycatch test fails.
Solution:   When calling function fails only check for following command, do
            not give another error.
diff --git a/src/userfunc.c b/src/userfunc.c
index d1d497d..fc2161f 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -3560,8 +3560,11 @@
 	// Check for trailing illegal characters and a following command.
 	if (!ends_excmd(*arg))
 	{
-	    emsg_severe = TRUE;
-	    emsg(_(e_trailing));
+	    if (!failed)
+	    {
+		emsg_severe = TRUE;
+		emsg(_(e_trailing));
+	    }
 	}
 	else
 	    eap->nextcmd = check_nextcmd(arg);