Add support for Shelly Dimmer 2 (#2954)

Co-authored-by: Niclas Larsson <niclas@edgesystems.se>
Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>
Co-authored-by: Jernej Kos <jernej@kos.mx>
Co-authored-by: Richard Nauber <richard@nauber.dev>

esphome/core/defines.h

@@ -93,3 +93,9 @@
 //#define USE_BSEC  // Requires a library with proprietary license.
 
 #define USE_DASHBOARD_IMPORT
+
+// Dummy firmware payload for shelly_dimmer
+#define USE_SHD_FIRMWARE_MAJOR_VERSION 56
+#define USE_SHD_FIRMWARE_MINOR_VERSION 5
+#define USE_SHD_FIRMWARE_DATA \
+  {}