Do not use inline styles, scripts and image in dependency-check-report.html due to CSP

Currently, the Gradle generated dependency-check-report.html holds inline-styles and scripts.
This is blocked by CSP if you serve the file by a server, like via Jenkins publishHTML.

The only way to get the page working currently is to lower CSP by

`style-src 'self' 'unsafe-inline'` and for script-src (this is strongly disscuraged)

Better is to externalize the styles, scripts and images into separate files and reference in dependency-check-report.html

Only possible way is to download the report html to get it working.