Leverage dependabot for automatic dependency management including Tomcat dependencies

This is a bit convoluted since this is a very specific case where we consume different dependency versions in different modules.

What needs to be done is that:

• properties may need to be removed from main pom.xml (well fwiw to prevent multiple rebases and reruns),
• properties need to be pushed to separate modules,
• the properties seem to require different name for this to work
• each tomcat module needs a specific dependabot configuration with upper limits set