fix: repair broken markdown in recipe-onboarding step 6

[hobostay]

Summary

• Fix broken markdown formatting in Step 6 ("Deploy Your First Resource") of google-cloud-recipe-onboarding/SKILL.md
• The list items were concatenated on the same lines with dashes instead of proper bullet point formatting
• The code block had trailing whitespace and incorrect indentation that could break rendering
• Properly format the three deployment options as distinct bullet points and fix the code block indentation

Before

The list rendered as a single concatenated paragraph. The code block had extra spaces and broken line continuations.

After

Three distinct bullet points for Cloud Run, Compute Engine, and Cloud Storage, with a properly formatted code block.

Test plan

• Verify the markdown renders correctly with proper bullet points and code block

🤖 Generated with Claude Code

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