transifex-client went EOL on November 30, 2022, replaced by
transifex/cli [^1].
Swap this in-place, since per the upstream README [^2]:
> The current version of the client maintains backwards compatibility
> for the tx push and tx pull commands. So, if you have a CI setup that
> uses them, you should not have to change anything.
As the mobile team found out, this is a partial truth if one previously
used some of the more advanced CLI flags, but all workflows referenced
in tools/ and docs/ use forwards-compatible flags to the new version.
[^1]: https://github.com/transifex/transifex-client/
[^2]: a0f28a1cf3/README.md
Anders Kaseorg
Josh Klar