v1.0.0: chore: update LICENSE-UNICODE to Unicode License v3

What's Changed

• feat: add case folding by @fgdorais in #3
• fix: change 'Batteries' to 'batteries' in lakefile by @fgdorais in #16
• fix: rename CaseFolding.getFull by @fgdorais in #19
• chore: update Unicode data to 18.0.0 by @fgdorais in #18
• chore: update LICENSE-UNICODE to Unicode License v3 by @fgdorais in #23

Full Changelog: https://github.com/fgdorais/lean4-unicode-data/commits/v1.0.0