We also add that the `do-all-signing` script currently does not run
`./macos-signer-proxy`.

- also update code_audit.sh to also print a commit's message/hash
  for further investigation, save reports in script directory, a
  renamed reports to include repo folder name, added cc and hh
  file extensions to c/cpp filter, changed arg order to make it
  easer to change filter for same commit range

Substitute placeholders `esrA` and `esrB` with actual commit hashes.
`esrA` is replaced with the commit tagged as
tor-browser-68.12.0esr-10.0-1-build1, and `esrB` is replaced as the last
audited commit for 78.6.1esr (tagged on FIREFOX_ESR_78_6_X_RELBRANCH).