Bump io.papermc.paper:paper-api

Bumps io.papermc.paper:paper-api from 1.20.4-R0.1-SNAPSHOT to 1.21.5-R0.1-SNAPSHOT.

---
updated-dependencies:
- dependency-name: io.papermc.paper:paper-api
  dependency-version: 1.21.5-R0.1-SNAPSHOT
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pom.xml

@@ -75,7 +75,7 @@
         <dependency>
             <groupId>io.papermc.paper</groupId>
             <artifactId>paper-api</artifactId>
-            <version>1.20.4-R0.1-SNAPSHOT</version>
+            <version>1.21.5-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
         <dependency>