[RELEASE] Released version 3.1-dev6

[RELEASE] Released version 3.1-dev6

Released version 3.1-dev6 with the following main changes :
    - BUG/MINOR: proto_tcp: delete fd from fdtab if listen() fails
    - BUG/MINOR: proto_tcp: keep error msg if listen() fails
    - MINOR: proto_tcp: tcp_bind_listener: copy errno in errmsg
    - MINOR: channel: implement ci_insert() function
    - BUG/MEDIUM: mworker/cli: fix pipelined modes on master CLI
    - REGTESTS: mcli: test the pipelined commands on master CLI
    - MINOR: cfgparse: load_cfg_in_mem: fix null ptr dereference reported by coverity
    - MINOR: startup: fix unused value reported by coverity
    - BUG/MINOR: mux-quic: do not send too big MAX_STREAMS ID
    - BUG/MINOR: proto_uxst: delete fd from fdtab if listen() fails
    - BUG/MINOR: cfgparse: parse_cfg: fix null ptr dereference reported by coverity
    - MINOR: proto_uxst: copy errno in errmsg for syscalls
    - MINOR: mux-quic: do not trace error in qcc_send_frames() on empty list
    - BUG/MINOR: h3: properly reject too long header responses
    - CLEANUP: mworker/cli: clean up the mode handling
    - BUG/MINOR: tools: make fgets_from_mem() stop at the end of the input
    - BUG/MINOR: pattern: pat_ref_set: fix UAF reported by coverity
    - BUG/MINOR: pattern: pat_ref_set: return 0 if err was found
    - CI: keep logs for failed QIUC Interop jobs
    - BUG/MINOR: release-estimator: fix relative scheme in CHANGELOG URL
    - MINOR: release-estimator: add requirements.txt
    -  MINOR: release-estimator: add installation steps in README.md
    - MINOR: release-estimator: fix the shebang of the python script
    - DOC: config: correct the table for option tcplog
    - MEDIUM: log: relax some checks and emit diag warnings instead in lf_expr_postcheck()
    - MINOR: log: "drop" support for log-profile steps
    - CI: QUIC Interop LibreSSL: document chacha20 test status
    - CI: modernize codespell action, switch to node 16
    - CI: QUIC Interop AWS-LC: enable chrome client
    - DOC: lua: fix incorrect english in lua.txt
    - MINOR: Implements new log format of option tcplog clf
    - MINOR: cfgparse: limit file size loaded via /dev/stdin
    - BUG/MINOR: stats: fix color of input elements in dark mode
    - CLEANUP: stats: use modern DOCTYPE tag
    - BUG/MINOR: stats: add lang attribute to html tag
    - DOC: quic: fix default minimal value for max window size
    - DOC: quic: document nocc debug congestion algorithm
    - MINOR: quic: extract config window-size parsing
    - MINOR: quic: define max-window-size config setting
    - MINOR: quic: allocate stream txbuf via qc_stream_desc API
    - MINOR: mux-quic: account stream txbuf in QCC
    - MEDIUM: mux-quic: implement API to ignore txbuf limit for some streams
    - MINOR: h3: mark control stream as metadata
    - MINOR: mux-quic: define buf_in_flight
    - MAJOR: mux-quic: allocate Tx buffers based on congestion window
    - MINOR: quic/config: adapt settings to new conn buffer limit
    - MINOR: quic: define sbuf pool
    - MINOR: quic: support sbuf allocation in quic_stream
    - MEDIUM: h3: allocate small buffers for headers frames
    - MINOR: mux-quic: retry after small buf alloc failure
    - BUG/MINOR: cfgparse-global: fix err msg in mworker keyword parser
    - BUG/MINOR: cfgparse-global: clean common_kw_list
    - BUG/MINOR: cfgparse-global: remove redundant goto
    - MINOR: cfgparse-global: move 'pidfile' in global keywords list
    - MINOR: cfgparse-global: move 'expose-*' in global keywords list
    - MINOR: cfgparse-global: move tune options in global keywords list
    - MINOR: cfgparse-global: move unsupported keywords in global list
    - BUG/MINOR: cfgparse-global: remove tune.fast-forward from common_kw_list
    - MINOR: quic: store the lost packets counter in the quic_cc_event element
    - MINOR: quic: support a tolerance for spurious losses
    - MINOR: protocol: properly assign the sock_domain and sock_family
    - MINOR: protocol: add a family lookup
    - MEDIUM: socket: always properly use the sock_domain for requested families
    - MINOR: protocol: add the real address family to the protocol
    - MINOR: socket: don't ban all custom families from reuseport
    - MINOR: protocol: always initialize the receivers list on registration
    - CLEANUP: protocol: no longer initialize .receivers nor .nb_receivers