Skip sandbox setup for syntax-only jobs

[MikeMcQuaid]

• Avoid Bubblewrap configuration for test-bot modes that do not run sandboxed formula install or test commands.
• Keep sandbox setup for formula-only jobs because they can execute sandboxed formula work.

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[github-code-quality]

Code Coverage Overview

Languages: Ruby

Ruby / code-coverage/simplecov

The overall coverage in the test-bot-sandbox-onl... branch remains at 78%, unchanged from the main branch.

Show a code coverage summary of the most impacted files.

File	main 43039a4	test-bot-sandbox-onl... 2e8d88a	+/-
utils/tty.rb	91%	92%	+1%
download_queue.rb	73%	74%	+1%
test_bot.rb	88%	93%	+5%

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_{Updated June 01, 2026 20:28 UTC
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