fix(onboarding): Prevent entire docs object from rendering as React child

[sentry]

This PR addresses an issue where the entire docs configuration object was being passed as a React child, leading to a runtime error: "Objects are not valid as a React child".

The root cause was identified as a combination of:

1. The docs object (specifically for Elixir, but potentially other platforms) not strictly conforming to the Docs interface, allowing non-step objects to be returned by install, configure, or verify functions.
2. Insufficient defensive checks in OnboardingLayout, Step.tsx, and ContentBlocksRenderer to handle such malformed inputs.

To fix this, the following changes were implemented:

• static/app/components/onboarding/gettingStartedDoc/contentBlocks/utils.tsx: Added checks in renderBlocks to ensure contentBlocks is an array and each block is a valid object with a string type and a registered renderer. Malformed blocks are now skipped.
• static/app/components/onboarding/gettingStartedDoc/step.tsx: Ensured that the content prop passed to ContentBlocksRenderer is always an array, coercing it to an empty array if it's not.
• static/app/components/onboarding/gettingStartedDoc/onboardingLayout.tsx: Introduced a safeCall helper to wrap calls to doc.install, doc.configure, and doc.verify. This helper ensures that these functions are called only if they exist and that their return values are arrays of OnboardingSteps. Additionally, a defensive check was added within the steps.map loop to skip rendering any step object that does not have a valid title or type string, preventing the entire Docs literal from being spread into <StyledStep />.

These changes make the onboarding rendering process more robust by defensively validating the shape of the docs configuration and ensuring that only valid React nodes or OnboardingStep objects are processed for rendering.

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Fixes JEST-28H7

[github-actions]

📊 Type Coverage Diff

✅ No new type safety issues introduced. Coverage: 93.56%