full-day workshop: Standardize code security settings navigation

Problem

content/full-day/1-code-scanning.md sends learners to Settings > Code security, but the Secret scanning and Code scanning sections then refer to Settings > Code security and analysis. A learner following the same page is given two names for the same settings destination.

The screenshots and labels are particularly important here because the controls vary with repository visibility and account features.

Suggested change

Verify the current GitHub settings experience and use one consistent navigation path throughout the exercise. Note any visibility or plan-dependent differences where needed.

Acceptance criteria

• Dependabot, secret scanning, push protection, and CodeQL steps use current, consistent settings labels.
• Screenshots match the labels used in the text.
• The exercise states what learners should expect when a control is already enabled or unavailable.
• The flow is validated in a public repository created from the template.

Start with content/full-day/1-code-scanning.md and verify the current GitHub settings experience in a public repository created from the template. Trace the Dependabot, secret scanning, push protection, and CodeQL steps, then align their labels and screenshots and document already-enabled or unavailable controls. Done means the full exercise uses consistent, current navigation and has been validated in the template repository.