Use ADC sampling

Use esphome/esphome#6330 to enable sampling on adc sensor and smooth the data.
Solves #1918

esphome/nspanel_esphome_core.yaml

@@ -36,7 +36,14 @@ external_components:
       url: https://github.com/edwardtfn/esphome
       ref: nextion-23  # To do: nextion-v425
     components:
-      - nextion  # Change this when that PR#6192 gets released (2024.3?)
+      - nextion  # Change this when that PR#6192 gets released (2024.4?)
+    refresh: 300s
+  - source:
+      type: git
+      url: https://github.com/edwardtfn/esphome
+      ref: adc-sampling
+    components:
+      - adc  # Change this when PR#6330 is merged (2024.4?)
     refresh: 300s
 
 ##### ESPHOME CONFIGURATION #####
@@ -1434,6 +1441,7 @@ sensor:
     pin: 38
     update_interval: 60s
     attenuation: 11db
+    samples: 12
 
   ##### INTERNAL TEMPERATURE SENSOR, adc reading converted to resistance (calculation)#####
   - id: resistance_sensor