[xhamster] Initials RegEx changed

[TheRealDude2]

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• Bug fix
• Improvement
• New extractor
• New feature

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Description of your pull request and other information

I noticed a problem again with the RegEx for the site initials, with patch #26254. As it looks like the web server has problems to deliver the line completely. On the other hand, the character ; appears more often in the line now.

I have tested a few lines:

• original version
  r'window.initials\s*=\s*({.+?})\s*;', webpage, 'initials',
• minimal change
  r'window.initials\s*=\s*({.+?})\s*;<', webpage, 'initials', #minimal changed
• full <script> tag parse
  r'<script\sid='initials-script'>window.initials\s=\s*({.+?})\s*;</script>', webpage, 'initials',
• parse until script end tag
  r'window.initials\s*=\s*({.+?})\s*;\s*</script>', webpage, 'initials',

I prefer the last one. i think this is the most robust version for changes to the line on the website.

Closes #26353