DynamicMacros: Do not read past storage_size_ when updating our map

When updating our map via Focus, do not read past `storage_size_`, because we do
not want to clobber storage space past our slice by accident.

Signed-off-by: Gergely Nagy <algernon@keyboard.io>

plugins/Kaleidoscope-DynamicMacros/src/kaleidoscope/plugin/DynamicMacros.cpp

@@ -272,7 +272,7 @@ EventHandlerResult DynamicMacros::onFocusEvent(const char *command) {
     } else {
       uint16_t pos = 0;
 
-      while (!::Focus.isEOL()) {
+      while (!::Focus.isEOL() && pos < storage_size_) {
         uint8_t b;
         ::Focus.read(b);