pw-check-override: add tool for creating patchwork checks

When builder gets out of whack and fails builds for internal reasons
contest will stop ingesting those patches. Add a tool which can
override checks on a patch. Override really means add a new check,
patchwork doesn't support delete or update of an existing check.

The tool also allows printing checks which may be convenient
(when check to add is not specified):

 $ ./pw-check-override -p 13728978
 Patch 13728978:
   Subject: [net,v2,2/5] octeontx2-af: fix a issue with cpt_lf_alloc mailbox
   Checks:
      0 2024-07-10 10:06 - success    series_format
      1 2024-07-10 10:06 - success    tree_selection
      2 2024-07-10 10:06 - success    ynl
      3 2024-07-10 10:06 - success    fixes_present
      4 2024-07-10 10:06 - success    header_inline
      5 2024-07-10 10:06 - success    build_32bit
      6 2024-07-10 10:06 - success    build_tools
      7 2024-07-10 10:06 - success    cc_maintainers
      8 2024-07-10 10:06 - success    build_clang
      9 2024-07-10 10:06 - success    verify_signedoff
     10 2024-07-10 10:06 - success    deprecated_api
     11 2024-07-10 10:06 - success    check_selftest
     12 2024-07-10 10:06 - success    verify_fixes
     13 2024-07-10 10:06 - success    build_allmodconfig_warn
     14 2024-07-10 10:06 - success    checkpatch
     15 2024-07-10 10:06 - success    build_clang_rust
     16 2024-07-10 10:06 - success    kdoc
     17 2024-07-10 10:06 - success    source_inline
     18 2024-07-10 11:02 - pending    contest
     19 2024-07-10 12:36 - fail       contest
     20 2024-07-10 12:44 - fail       contest
     21 2024-07-10 13:08 - fail       contest
     22 2024-07-10 16:07 - success    contest

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>