[RELEASE] Released version 2.5.4

[RELEASE] Released version 2.5.4

Released version 2.5.4 with the following main changes :
    - BUG/MEDIUM: htx: Be sure to have a buffer to perform a raw copy of a message
    - BUG/MEDIUM: mux-h1: Don't wake h1s if mux is blocked on lack of output buffer
    - BUG/MAJOR: mux-h2: Be sure to always report HTX parsing error to the app layer
    - DOC: Fix usage/examples of deprecated ACLs
    - BUG/MINOR: proxy: preset the error message pointer to NULL in parse_new_proxy()
    - REGTESTS: fix the race conditions in 40be_2srv_odd_health_checks
    - CI: github: enable pool debugging by default
    - BUG/MEDIUM: stream: Abort processing if response buffer allocation fails