Discuss greasing the QUIC Bit (as an unencrypted field)

[gorryfair]

We mentioned that QUIC also had non-encrypted examples that could be used relating to greasing.

[LPardue]

@gorryfair can you propose some text?

[martinthomson]

See my comments on #53. RFC 9287 is not encrypted.

[tfpauly]

This mainly is "mention greasing the QUIC Bit" https://www.rfc-editor.org/rfc/rfc9287.html

[tfpauly]

Having trouble finding a good spot to mention this, at the moment — this may be good to mention in a broader new section about wire images.