Replace truststore password with a generated password.

[mshima]

Overview of the issue

See https://sonarcloud.io/project/issues?impactSoftwareQualities=SECURITY&issueStatuses=OPEN%2CCONFIRMED&id=jhipster-sample-application&open=AY-bGbmy0r5EG8xkTIvB

Motivation for or Use Case

Fix sonar issue and improve security of out of box application.

Reproduce the error

Related issues

Suggest a Fix

Generate a random password like jwtSecretKey or use base name as password.

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