Matter improve encoding of attributes to reduce flash size

[s-hadinger]

Description:

Matter change the internal encoding of attributes per clusters to use bytes instead of arrays. Not functional change.

Size code reduction: 17.8KB

Details:

Before, attributes were encoded with a map of lists:

{
  768: [0, 1, 0xFFF9, 0xFFFA, 0xFFFB, 0xFFFC, 0xFFFD],
 [...]
}

Now attributes are in a packed bytes buffer of 16-bit unsigned integers in Big Endian:

{
  768: bytes('00000001FFF9FFFAFFFBFFFCFFFD'),
 [...]
}

Checklist:

• The pull request is done against the latest development branch
• Only relevant files were touched
• Only one feature/fix was added per PR and the code change compiles without warnings
• The code change is tested and works with Tasmota core ESP8266 V.2.7.7
• The code change is tested and works with Tasmota core ESP32 V.3.0.2
• I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass