Upgrade HerdDB to 0.19.0 (apache#330)

### Motivation
Upgrade HerdDB to 0.19.0, especially because it contains a new version of diskless-cluster mode, a mode in which all data is stored on Bookies and not on local disks.

see https://github.com/diennea/herddb/wiki/Installing-and-running-HerdDB for reference


### Modifications
Upgrade HerdDB to 0.19.0

### Verifying this change

- [X] Make sure that the change passes the `./gradlew build` checks.

gradle.properties

@@ -17,7 +17,7 @@ apiMockitoVersion=1.7.1
 mockitoJunit4Version=1.7.1
 gsonVersion=2.8.2
 postgresqlVersion=42.2.5
-herddbVersion=0.16.1
+herddbVersion=0.19.0
 brokerVersion=2.4.1
 commonsValidatorVersion=1.6
 bkvmVersion=1.2.0