Use the configured temp folder for dumping instrumented class files in debug mode.

core/src/main/java/com/zaxxer/hikari/javassist/HikariClassTransformer.java

@@ -212,7 +212,7 @@ public class HikariClassTransformer implements ClassFileTransformer
 
         if (LOGGER.isDebugEnabled())
         {
-            target.debugWriteFile("/tmp");
+            target.debugWriteFile(System.getProperty("java.io.tmpdir"));
         }
         return target.toBytecode();
     }