Update yaml-cpp

[adisuissa]

Title: Update yaml-cpp

Description:
Recent additions to yaml-cpp help with some fuzz issues corner cases (example, #20544).
The yaml-cpp lib in Envoy was last updated in July 2021, and we should upgrade it to the latest main sha

[adisuissa]

Fixed by #20886, closing.

[vehre-x41]

@adisuissa this can be closed, too, right?

[vehre-x41]

Whoops, should have reloaded first. Sorry, for the noise.