Fix lint

Author: fortuna

.github/workflows/esphome-validate.yaml

@@ -29,4 +29,4 @@ jobs:
       - name: Compile demos
         env:
           PLATFORMIO_BUILD_CACHE_DIR: /tmp/esphome_cache_${{ github.run_id }}
-        run: esphome config boards/*/demo.yaml
+        run: esphome build boards/*/demo.yaml

boards/m5stack-atom-echo/demo.yaml

@@ -38,6 +38,6 @@ rtttl:
   - id: rtttl_player
     speaker: echo_speaker
     gain: 0.3
-    on_finished_playback: 
+    on_finished_playback:
       then:
         - logger.log: Finished playing RTTTL tune.