Bump com.anthropic:anthropic-java from 2.7.0 to 2.8.1

Bumps [com.anthropic:anthropic-java](https://github.com/anthropics/anthropic-sdk-java) from 2.7.0 to 2.8.1.
- [Release notes](https://github.com/anthropics/anthropic-sdk-java/releases)
- [Changelog](https://github.com/anthropics/anthropic-sdk-java/blob/main/CHANGELOG.md)
- [Commits](anthropics/anthropic-sdk-java@v2.7.0...v2.8.1)

---
updated-dependencies:
- dependency-name: com.anthropic:anthropic-java
  dependency-version: 2.8.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -21,7 +21,7 @@ awaitility = "4.3.0"
 
 # Samples
 mcp-kotlin = "0.7.2"
-anthropic = "2.7.0"
+anthropic = "2.8.1"
 shadow = "8.1.1"
 
 [libraries]