patch 9.0.1876: Vim9: parsing commands with newlines wrong

Problem:  Vim9: parsing commands with newlines wrong
Solution: Accept a '\n' for parsing lists and command arguments

closes: #13015
closes: #13020

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 10d979d..d4b972a 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -3954,7 +3954,7 @@
 #ifdef FEAT_EVAL
     if (eap->cmdidx < CMD_SIZE
 	    && vim9
-	    && !IS_WHITE_OR_NUL(*p) && *p != '\n' && *p != '!' && *p != '|'
+	    && !IS_WHITE_NL_OR_NUL(*p) && *p != '!' && *p != '|'
 	    && (eap->cmdidx < 0 ||
 		(cmdnames[eap->cmdidx].cmd_argt & EX_NONWHITE_OK) == 0))
     {