Investigate a better way to handle non-interactive use of setup_conda.sh

[mkavulich]

Description

Per discussion in PR 25, setup_conda.sh contains some user prompts that rely on silent failures to continue when run from a non-interactive shell (e.g. from submitted jobs, crontabs, etc.).

Solution

It may be preferable to have different explicit behavior for interactive vs non-interactive shells

Requirements

See PR 25 discussion

Acceptance Criteria

See PR 25 discussion