Berry add introspect.contains and bytes.addfloat

[s-hadinger]

Description:

Berry add:

• introspect.contains(any, member:string) -> bool: returns true if the instance/class/module contains the member
• bytes().addfloat(val: float [, big_endian:bool]) -> bytes instance: add the 32 bit float to the buffer, default is little-endian except if true is passed as second argument.

These extensions are useful for future LVGL 9 integration.

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.2.7.6
• The code change is tested and works with Tasmota core ESP32 V.2.0.14
• I accept the CLA.

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