Tomcat JAVA_HOME environment not working for OpenJDK

[smalenfant]

I have openjdk installed and traffic router would not start.

In /usr/lib/systemd/system/traffic_router.service, the following is configured and doesn't exist:

Environment=JAVA_HOME=/usr/lib/jvm/java
```

It should be changed to `Environment=JAVA_HOME=/usr/lib/jvm/jre`

```
# rpm -qa | grep openjdk
java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64
java-1.8.0-openjdk-headless-1.8.0.191.b12-0.el7_5.x86_64
```

```
# ls -l /usr/lib/jvm
total 0
drwxr-xr-x 3 root root 17 Nov 12 12:50 java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64
lrwxrwxrwx 1 root root 21 Nov 12 12:50 jre -> /etc/alternatives/jre
lrwxrwxrwx 1 root root 27 Nov 12 12:50 jre-1.8.0 -> /etc/alternatives/jre_1.8.0
lrwxrwxrwx 1 root root 35 Nov 12 12:50 jre-1.8.0-openjdk -> /etc/alternatives/jre_1.8.0_openjdk
lrwxrwxrwx 1 root root 51 Nov 12 12:50 jre-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64 -> java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64/jre
lrwxrwxrwx 1 root root 29 Nov 12 12:50 jre-openjdk -> /etc/alternatives/jre_openjdk
```