[L] Change in flashrom[main]: doc: Release notes for version 1.4.0

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Alexander Goncharov, Nikolai Artemiev, Peter Marheine, Stefan Reinauer.

Anastasia Klimchuk has posted comments on this change by Anastasia Klimchuk. ( https://review.coreboot.org/c/flashrom/+/83359?usp=email )

Change subject: doc: Release notes for version 1.4.0
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Patch Set 4:

(1 comment)

File doc/release_notes/v_1_4.rst:

https://review.coreboot.org/c/flashrom/+/83359/comment/b566e359_ec2c5803?usp... :
PS3, Line 55: used
> Typo (my fault?): use […]

Thanks, done!

I also added one more line in the last section, misc. Somehow I missed it earlier: renaming branch from master to main.
Not a user-facing feature, but for developers this has information. Especially if someone happens to not updated the repository from a year ago.