Fix intermittent crash when capturing screenshots due to invalid viewport

[tustanivsky]

This PR adds a null check to the screenshot capturing utility to prevent intermittent crashes when the game viewport is not initialized.

Closes #1329

[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

📋 Changelog Preview

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Bug Fixes 🐛

• Prevent potential script injection in crash-reporter-build workflow by fix-it-felix-sentry in #1324

Internal Changes 🔧

• (deps) Update CLI to v3.3.5 by github-actions in #1323
• Update validate-pr workflow by stephanie-anderson in #1328

Other

• Fix intermittent crash when capturing screenshots due to invalid viewport by tustanivsky in #1331

• Suppress superfluous warnings when detecting for SteamOS by yangskyboxlabs in #1326
• Add out-of-process screenshot capturing on Windows by tustanivsky in #1325

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