[dependency-track] support volume mounts

[heiko-ma]

Is your feature request related to a problem? Please describe.
When deploying the helm chart, there is no possibility to mount additional volumes, e.g. for secret files. We are using ssl inspection in our company network so the container needs to know our company ca certificates.

Describe the solution you'd like
It would be nice if there was a section in the helm chart which supports mouting volumes, secrets or config maps. Imo this should be fairly easy to implement.