Fix some serial char, echo

Co-Authored-By: X-Ryl669 <3277165+X-Ryl669@users.noreply.github.com>

Marlin/src/feature/bedlevel/bedlevel.cpp

@@ -196,7 +196,7 @@ void reset_bed_level() {
         #endif
       }
       #ifdef SCAD_MESH_OUTPUT
-        SERIAL_CHAR(' ', ']');            // close sub-array
+        SERIAL_ECHOPGM(" ]");            // close sub-array
         if (y < sy - 1) SERIAL_CHAR(',');
       #endif
       SERIAL_EOL();