[RELEASE] Released version 2.4-dev2

Released version 2.4-dev2 with the following main changes :
    - BUILD: Make DEBUG part of .build_opts
    - BUILD: Show the value of DEBUG= in haproxy -vv
    - CI: Set DEBUG=-DDEBUG_STRICT=1 in GitHub Actions
    - MINOR: stream: Add level 7 retries on http error 401, 403
    - CLEANUP: remove unused function "ssl_sock_is_ckch_valid"
    - BUILD: SSL: add BoringSSL guarding to "RAND_keep_random_devices_open"
    - BUILD: SSL: do not "update" BoringSSL version equivalent anymore
    - BUG/MEDIUM: http_act: Restore init of log-format list
    - DOC: better describes how to configure a fallback crt
    - BUG/MAJOR: filters: Always keep all offsets up to date during data filtering
    - MINOR: cache: Prepare helper functions for Vary support
    - MEDIUM: cache: Add the Vary header support
    - MINOR: cache: Add a process-vary option that can enable/disable Vary processing
    - BUG/CRITICAL: cache: Fix trivial crash by sending accept-encoding header
    - BUG/MAJOR: peers: fix partial message decoding
    - DOC: cache: Add new caching limitation information
    - DOC: cache: Add information about Vary support
    - DOC: better document the config file format and escaping/quoting rules
    - DOC: Clarify %HP description in log-format
    - CI: github actions: update LibreSSL to 3.3.0
    - CI: github actions: enable 51degrees feature
    - MINOR: fd/threads: silence a build warning with threads disabled
    - BUG/MINOR: tcpcheck: Don't forget to reset tcp-check flags on new kind of check
    - MINOR: tcpcheck: Don't handle anymore in-progress send rules in tcpcheck_main
    - BUG/MAJOR: tcpcheck: Allocate input and output buffers from the buffer pool
    - MINOR: tcpcheck: Don't handle anymore in-progress connect rules in tcpcheck_main
    - MINOR: config: Deprecate and ignore tune.chksize global option
    - MINOR: config: Add a warning if tune.chksize is used
    - REORG: tcpcheck: Move check option parsing functions based on tcp-check
    - MINOR: check: Always increment check health counter on CONPASS
    - MINOR: tcpcheck: Add support of L7OKC on expect rules error-status argument
    - DOC: config: Make disable-on-404 option clearer on transition conditions
    - DOC: config: Move req.hdrs and req.hdrs_bin in L7 samples fetches section
    - BUG/MINOR: http-fetch: Fix smp_fetch_body() when called from a health-check
    - MINOR: plock: use an ARMv8 instruction barrier for the pause instruction
    - MINOR: debug: add "debug dev sched" to stress the scheduler.
    - MINOR: debug: add a trivial PRNG for scheduler stress-tests
    - BUG/MEDIUM: lists: Lock the element while we check if it is in a list.
    - MINOR: task: remove tasklet_insert_into_tasklet_list()
    - MINOR: task: perform atomic counter increments only once per wakeup
    - MINOR: task: remove __tasklet_remove_from_tasklet_list()
    - BUG/MEDIUM: task: close a possible data race condition on a tasklet's list link
    - BUG/MEDIUM: local log format regression.
4 files changed