[travis] Add missing `truststore` to CrateDB docker setup
[travis] Add missing `truststore` to CrateDB docker setup

The `truststore` path mapping was missing on the docker run command
and thus SSL connections to CrateDB didn't work.

Before CrateDB 4.2.x, a custom truststore was generated on node startup
and the `ssl.truststore_filepath` setting wasn’t required.

Relates https://github.com/crate/crate/pull/9690.
crate/crate-pdo,crate/crate-pdo