Add license rule for LGPL-3.0-or-later notice pattern

[harpreet-2146]

Fixes #3935

Adds detection rule for the license notice pattern:
'Distributed under the terms of the GNU Lesser General Public License,
either version 3 of the License, or (at your option) any later version.'

This pattern was previously misdetected as lgpl-2.1-plus due to partial matching of 'GNU Lesser General Public License' without the version 3 context. The new rule matches the complete two-line notice and correctly identifies it as lgpl-3.0-plus.

Testing done:

• Created test file with the exact pattern from issue LGPL-3.0-or-later wrongly identified as GPL-2.0-or-later #3935
• Verified detection changed from lgpl-2.1-plus AND lgpl-3.0-plus to just lgpl-3.0-plus
• Rule passes scancode-reindex-licenses

Tasks

• Reviewed contribution guidelines
• PR is descriptively titled 📑 and links the original issue above 🔗
• Tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR
• Commits are in uniquely-named feature branch and has no merge conflicts 📁
• Updated documentation pages (if applicable)
• Updated CHANGELOG.rst (if applicable)

Signed-off-by: Harpreet Kaur Gothra [email protected]