I found the Tomcat Version in Catalina log.
In my Environment I found the log in: \VMware\vCenterServer\logs\vsm\web\
In the latest catalina.2017-08-29.log
...
29-Aug-2017 14:28:42.988 INFO [WrapperSimpleAppMain] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Pivotal tc Runtime 3.1.5.RELEASE/8.0.36.A.RELEASE
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