patch 8.2.0612: Vim9: no check for space before #comment

Problem:    Vim9: no check for space before #comment.
Solution:   Add space checks.
diff --git a/src/highlight.c b/src/highlight.c
index ee2e437..9476a7d 100644
--- a/src/highlight.c
+++ b/src/highlight.c
@@ -658,7 +658,7 @@
     /*
      * If no argument, list current highlighting.
      */
-    if (ends_excmd(*line))
+    if (!init && ends_excmd2(line - 1, line))
     {
 	for (i = 1; i <= highlight_ga.ga_len && !got_int; ++i)
 	    // TODO: only call when the group has attributes set