Shell session sometimes executes in `/bin/bash` instead of bundled Bash

[gerlero]

The shell session is being executed by the system's /bin/bash instead of the bundled Bash at /Volumes/OpenFOAM-vXXXX/env/bin/bash, leading to the following message:

The default interactive shell is now zsh.
To update your account to use zsh, please run `chsh -s /bin/zsh`.
For more details, please visit https://support.apple.com/kb/HT208050.

[gerlero]

NOTE: only happens if OpenFOAM is already activated at the time the etc/openfoam script is called. The reason is that the functionality that deactivates a previously active OpenFOAM install within etc/openfoam removes env/bin from the $PATH before calling bash.