Fix bug throwing exception when first event is collected

Fix bug throwing exception when first event is collected

- Problem: When running app from jar (e.g. in docker env) ClassLoader
badly interprete classpath as root of app jar, while resources are
located in jar under BOOT-INF/classes/ in Spring Boot apps.

- Solution: Moved file from resources to etc directory so ClassLoader
isn't needed. Filepath of api_version_description.json which
previously was badly resolved now is configured in collector.properties.

Change-Id: I690394cc59e16c95f5902045efc3fdaf13bf9112
Signed-off-by: Michal Banka <michal.banka@nokia.com>
Issue-ID: DCAEGEN2-2426