Upgrade http and llhttp-ffi

What does this MR do and why?

This MR upgrades the http gem from 5.1.1 to 5.3.1 and its dependency llhttp-ffi from 0.4.0 to 0.5.1 to fix a bug where all Geo blob replication fails with an HPE_USER Span callback error in on_header_field error on Ubuntu 24.04 instances running kernel 6.17.

This bug breaks all blob replication for Geo, because the BlobDownloader class uses the HTTP gem.

References

#595139

Gem diffs

http version 5.1.1 --> 5.3.1: https://github.com/httprb/http/compare/v5.1.1...v5.3.1

llhttp-ffi version 0.4.0 --> 0.5.1: https://github.com/bryanp/llhttp/compare/2021-09-09...2025-03-11

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