Update pocketmine/locale-data requirement from ~2.19.0 to ~2.20.0

Updates the requirements on [pocketmine/locale-data](https://github.com/pmmp/Language) to permit the latest version.
- [Commits](pmmp/Language@2.19.0...2.20.0)

---
updated-dependencies:
- dependency-name: pocketmine/locale-data
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -41,7 +41,7 @@
       "pocketmine/callback-validator": "^1.0.2",
       "pocketmine/color": "^0.3.0",
       "pocketmine/errorhandler": "^0.6.0",
-      "pocketmine/locale-data": "~2.19.0",
+      "pocketmine/locale-data": "~2.20.0",
       "pocketmine/log": "^0.4.0",
       "pocketmine/math": "~1.0.0",
       "pocketmine/nbt": "~1.0.0",