[Aurora] Adds custom metrics for Next.js

[housseindjirdeh]

Adds a few Next.js custom metrics:

• Next.js version
• Bool if Next.js Script component is used
• Bool if Next.js Third Parties lib is used
• Count of beforeInteractive Next scripts
• Count of afterInteractive Next scripts
• Count of lazyOnload Next scripts
• Count of worker Next scripts

Example WPT: https://www.webpagetest.org/result/240205_AiDc5H_D9P/2/details/

Test websites:

• https://www.mux.com/

CC @kara @janicklas-ralph

[github-actions[bot]]

Custom metrics for https://almanac.httparchive.org/en/2022/

WPT test run results: http://webpagetest.httparchive.org/results.php?test=240205_PJ_5

Custom metrics for https://www.mux.com/

WPT test run results: http://webpagetest.httparchive.org/results.php?test=240205_JF_6 Changed custom metrics values: ```json {} ```