[Infra] Make GitHub Actions `cpp-linux-arm64` test work with `actions/cpp-tests`

[rturrado]

We have recently moved to using pipx in the composite action. pipx installs conan. After changing to pipx, this job can no longer find conan.

Note: cpp-linux-arm64 job runs on a python:3.11 container on a self-hosted runner.

[rturrado]

I suppose the idea with this issue is to wait until we can run this job in a GitHub hosted runner.