Bump io.papermc.paper:paper-api

Bumps io.papermc.paper:paper-api from 1.21.8-R0.1-SNAPSHOT to 1.21.9-pre4-R0.1-SNAPSHOT.

---
updated-dependencies:
- dependency-name: io.papermc.paper:paper-api
  dependency-version: 1.21.9-pre4-R0.1-SNAPSHOT
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

build.gradle

@@ -29,7 +29,7 @@ dependencies {
 	shadow group: 'org.bstats', name: 'bstats-bukkit', version: '3.1.0'
 	shadow group: 'net.kyori', name: 'adventure-text-serializer-bungeecord', version: '4.4.1'
 
-	implementation group: 'io.papermc.paper', name: 'paper-api', version: '1.21.8-R0.1-SNAPSHOT'
+	implementation group: 'io.papermc.paper', name: 'paper-api', version: '1.21.9-pre4-R0.1-SNAPSHOT'
 	implementation group: 'com.google.code.findbugs', name: 'findbugs', version: '3.0.1'
 
 	// bundled with Minecraft 1.19.4+ for display entity transforms