runtime(doc): Fix notation of "Vim script" and "Vim9 script"

closes: #17213

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testing.c b/src/testing.c
index b316b64..cfa01ff 100644
--- a/src/testing.c
+++ b/src/testing.c
@@ -1411,7 +1411,7 @@
 	if (dict_get_bool(args, "cell", FALSE))
 	{
 	    // calculate the middle of the character cell
-	    // Note: Cell coordinates are 1-based from vimscript
+	    // Note: Cell coordinates are 1-based from Vim script
 	    pY = (row - 1) * gui.char_height + gui.char_height / 2;
 	    pX = (col - 1) * gui.char_width + gui.char_width / 2;
 	}