build(deps): bump com.badlogicgames.gdx:gdx-jnigen from 2.4.0 to 2.5.1

Bumps [com.badlogicgames.gdx:gdx-jnigen](https://github.com/libgdx/gdx-jnigen) from 2.4.0 to 2.5.1.
- [Release notes](https://github.com/libgdx/gdx-jnigen/releases)
- [Changelog](https://github.com/libgdx/gdx-jnigen/blob/master/CHANGES)
- [Commits](libgdx/gdx-jnigen@2.4.0...2.5.1)

---
updated-dependencies:
- dependency-name: com.badlogicgames.gdx:gdx-jnigen
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

buildSrc/build.gradle

@@ -7,7 +7,7 @@ repositories {
 }
 
 ext {
-    jnigenVersion = '2.4.0'
+    jnigenVersion = '2.5.1'
 }
 
 dependencies {