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 513c3d2	test-bot-sandbox-onl... 9a91b09	+/-
services/system.rb	85%	81%	-4%
services/cli.rb	63%	61%	-2%
bundle/extensio...de_extension.rb	99%	98%	-1%
test_bot.rb	88%	93%	+5%
services/system/systemctl.rb	87%	93%	+6%

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_{Updated June 02, 2026 14:34 UTC
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