Request: Add description of `tasmota-4M.bin` build to Firmware-Builds page

[DeflateAwning]

Relevant page: https://tasmota.github.io/docs/Firmware-Builds/

The firmware builds page doesn't explain what the "4M" variant is for. Would be great to add that piece of info to that page!

[barbudor]

Tasmota docs are open source and are maintained by the community, people like YOU
If you can't help tasmota with code, you can help with improving the documentation.
Thanks in advance for your support.

However the BUILDs page is a bit specific as it is copied from this arendst/tasmota/BUILDS.md page
Any edit/PR should be done there

[DeflateAwning]

Can you explain what the 4M variant is for so I can add it?