on_retry_command not respecting shell choice

[Ben Konicek]

Describe the bug
The on_retry_command input, when run, is not using the default or chosen shell from the action inputs. This is causing certain commands to fail

- name: Deploy
  uses: nick-fields/retry@v2.8.3
  with:
    retry_wait_seconds: 1
    max_attempts: 3
    timeout_minutes: 7
    command: |
      exit 1
    on_retry_command: |
      if [[ "foo" == "foo" ]]; then
        echo "result is true"
      fi

Error: /bin/sh: 1: [[: not found

Expected behavior
It should return result is true, and use bash as the shell, not sh

Screenshots
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Logs
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Debug logs: raw-debug-logs.txt