When logging TranslatableMarkup, arguments aren't substituted into the message

Test-only patch attached; should fail.

Test + fix patch attached; should pass.

The last submitted patch, 3: 3378594-jsonlog-translatable-3.patch, failed testing. View results →
- codesniffer_fixes.patch Interdiff of automated coding standards fixes only.

Updated for PHP 7.3 compatibility.

Updated patch to also handle regular (non-object) log messages.

The patch works but has unintended side-effects.
Namely, the new parameters `message_orig` and `message_args` leak into the logs.
Here is how the log looks now:

{
  "@timestamp": "2024-06-01T18:57:01.471Z",
  "@version": 1,
  "message": "event: unpublished asdf",
  "message_orig": "@type: @action @title",
  "message_args": {
    "@type": "event",
    "@action": "unpublished",
    "@title": "asdf"
  },
  "message_id": "4a5b318cb696665b6efd72f120.96887480",
  "site_id": "4a5b318cb696",
  "canonical": "...",
  "method": "GET",
  "tags": null,
  "type": "drupal",
  "subtype": "publishcontent",
  "severity": "Notice",
  "request_uri": "...",
  "referer": "...",
  "uid": 53,
  "username": null,
  "client_ip": "...",
  "link": null,
  "code": 0,
  "trunc": ""
}

I ended up with a bit simpler patch but it goes without tests.

Fixed file paths.

The patch works but has unintended side effects.
Namely, the new parameters message_orig and message_args leak into the logs.

@ragnarkurm, I intentionally included those values — when bulk-analyzing log messages, it's helpful to know which template was used (message_orig) in order to group together similar log messages, and it's helpful to have the individual argument values (message_args) in order to show them in columns and sort/filter them (otherwise the log analyzer needs to parse the formatted message in order to recover them).