fix: prevent RUNNER detection failure

[ZohebShaikh]

Append || true so the justfile can still be parsed/used on systems without a container runtime like docker or podman, instead of erroring out at command substitution time.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.34%. Comparing base (c0f6904) to head (714db00).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1647   +/-   ##
=======================================
  Coverage   96.34%   96.34%           
=======================================
  Files          46       46           
  Lines        3666     3666           
=======================================
  Hits         3532     3532           
  Misses        134      134           

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[tpoliaw]

Doesn't this just make it fail later with an arguably more cryptic compose: command not found?

It would be good to catch this though, maybe something like

RUNNER = `command -v docker || command -v podman || true`

_check-runner: 
    #!/usr/bin/env bash
    if [[ "{{ RUNNER }}" == "" ]]; then
        echo "No container runtime available - either podman or docker is required"
        exit 1
    fi

compose <... existing args ...>: _check-runner
    ...

This then fails with

$ just
No container runtime available - either podman or docker is required
error: recipe `_check-runner` failed with exit code 1