patch 8.2.1851: Vim9: "!" followed by space incorrectly used

Problem:    Vim9: "!" followed by space incorrectly used.
Solution:   Skip over trailing spaces. (closes #7131)
diff --git a/src/eval.c b/src/eval.c
index 58d98e5..9ef3128 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -3390,10 +3390,14 @@
 	f = rettv->vval.v_float;
     else
 #endif
+    {
+	while (VIM_ISWHITE(end_leader[-1]))
+	    --end_leader;
 	if (in_vim9script() && end_leader[-1] == '!')
 	    val = tv2bool(rettv);
 	else
 	    val = tv_get_number_chk(rettv, &error);
+    }
     if (error)
     {
 	clear_tv(rettv);