update serialversionuids in DatabaseAccessManager

src/main/java/org/caosdb/server/database/DatabaseAccessManager.java

@@ -52,7 +52,7 @@ import org.caosdb.server.utils.Releasable;
  */
 class ReadAccessSemaphore extends Semaphore implements Releasable {
 
-  private static final long serialVersionUID = -262226321839837533L;
+  private static final long serialVersionUID = 4384921156838881337L;
   private int acquired = 0; // how many thread have read access
   Semaphore block = new Semaphore(1, true);