refactor(plugin-lighthouse): update lighthouse and adopt tests

[BioPhoton]

Lighthouse v12 received significant changes see release notes.

[nx-cloud]

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✅ Successfully ran 6 targets

• nx release --yes --dry-run
• nx affected -t unit-test --parallel=3 --coverage.enabled
• nx affected:e2e --parallel=3
• nx affected -t integration-test --parallel=3 --coverage.enabled
• nx affected:lint --parallel=3
• nx affected:build --parallel=3

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[github-actions]

Code PushUp

🤨 Code PushUp report has both improvements and regressions – compared target commit 619d806 with source commit 8a1c834.

🏷️ Categories

🏷️ Category	⭐ Current score	⭐ Previous score	🔄 Score change
Performance	🟡 71	🟡 88
Accessibility	🟢 98	🟢 100
SEO	🟡 85	🟡 86
Updates	🟡 89	🟡 89
Code coverage	🟡 89	🟡 89
Best Practices	🟢 100	🟢 100	–
Bug prevention	🟢 100	🟢 100	–
Code style	🟢 99	🟢 99	–
Security	🟢 94	🟢 94	–
Custom checks	🟡 67	🟡 67	–

🗃️ Groups

👍 1 group improved, 👎 4 groups regressed

🔌 Plugin	🗃️ Group	⭐ Current score	⭐ Previous score	🔄 Score change
Lighthouse	Performance	🟡 71	🟡 88
Lighthouse	Accessibility	🟢 98	🟢 100
Lighthouse	SEO	🟡 85	🟡 86
JS Packages	NPM outdated dependencies	🟡 89	🟡 89
Code coverage	Code coverage metrics	🟡 89	🟡 89

15 other groups are unchanged.

🛡️ Audits

👍 5 audits improved, 👎 8 audits regressed, 10 audits changed without impacting score

🔌 Plugin	🛡️ Audit	📏 Current value	📏 Previous value	🔄 Value change
Lighthouse	Avoid large layout shifts	🟩 15 layout shifts found	🟥 15 layout shifts found
Lighthouse	Background and foreground colors have a sufficient contrast ratio	🟥 0	🟩 0
Lighthouse	Total Blocking Time	🟥 1,360 ms	🟩 130 ms
Lighthouse	Max Potential First Input Delay	🟥 520 ms	🟨 220 ms
Lighthouse	Cumulative Layout Shift	🟩 0.006	🟨 0.147
Lighthouse	Largest Contentful Paint	🟨 2.8 s	🟨 2.9 s
Lighthouse	Speed Index	🟩 2.6 s	🟩 1.5 s
JS Packages	Outdated NPM dev dependencies.	🟨 56 outdated package versions (26 major, 23 minor, 1 preminor, 5 patch, 1 prerelease)	🟨 57 outdated package versions (27 major, 24 minor, 5 patch, 1 prerelease)
Lighthouse	Time to Interactive	🟩 3.0 s	🟩 2.6 s
Lighthouse	First Contentful Paint	🟩 1.0 s	🟩 1.2 s
Code coverage	Branch coverage	🟨 83 %	🟨 83 %
Code coverage	Function coverage	🟩 91 %	🟩 91 %
Code coverage	Line coverage	🟩 91 %	🟩 91 %
Lighthouse	Avoids enormous network payloads	🟩 Total size was 431 KiB	🟩 Total size was 432 KiB
Lighthouse	Minimizes main-thread work	🟥 4.2 s	🟥 2.8 s
Lighthouse	Uses efficient cache policy on static assets	🟨 11 resources found	🟨 11 resources found
Lighthouse	Properly size images	🟥 Potential savings of 239 KiB	🟥 Potential savings of 240 KiB
Lighthouse	Metrics	🟩 2985	🟩 2647
Lighthouse	JavaScript execution time	🟩 0.1 s	🟩 0.1 s
Lighthouse	First Meaningful Paint	🟩 1.1 s	🟩 1.2 s
Lighthouse	Network Round Trip Times	🟩 20 ms	🟩 10 ms
Lighthouse	Server Backend Latencies	🟩 20 ms	🟩 20 ms
Lighthouse	Initial server response time was short	🟩 Root document took 0 ms	🟩 Root document took 10 ms

482 other audits are unchanged.

[matejchalk]

Thanks for the update 👍