Bump it.unimi.dsi:fastutil from 8.5.12 to 8.5.15

Bumps [it.unimi.dsi:fastutil](https://github.com/vigna/fastutil) from 8.5.12 to 8.5.15.
- [Changelog](https://github.com/vigna/fastutil/blob/master/CHANGES)
- [Commits](vigna/fastutil@8.5.12...8.5.15)

---
updated-dependencies:
- dependency-name: it.unimi.dsi:fastutil
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

pom.xml

@@ -300,7 +300,7 @@
 		<dependency>
 			<groupId>it.unimi.dsi</groupId>
 			<artifactId>fastutil</artifactId>
-			<version>8.5.12</version>
+			<version>8.5.15</version>
 		</dependency>
 		<dependency>
 			<groupId>net.jafama</groupId>