patch 8.2.3987: error messages are spread out

Problem:    Error messages are spread out.
Solution:   Move more error messages to errors.h.
diff --git a/src/netbeans.c b/src/netbeans.c
index 5bdb868..c4223ca 100644
--- a/src/netbeans.c
+++ b/src/netbeans.c
@@ -1941,7 +1941,7 @@
 	    bg = vim_strsave(p);
 	    if (STRLEN(fg) > MAX_COLOR_LENGTH || STRLEN(bg) > MAX_COLOR_LENGTH)
 	    {
-		emsg("E532: highlighting color name too long in defineAnnoType");
+		emsg(e_highlighting_color_name_too_long_in_defineAnnoType);
 		VIM_CLEAR(typeName);
 		parse_error = TRUE;
 	    }