Setting Maven Mirror URL does not exclude Business Central

If a user specifies a maven mirror url in the templates, then that mirror should exclude Business Central in it's "mirror of" config. Otherwise, maven in the KIE Server will attempt to look to Business Central for external artifacts.

To fix this, the following should be added to the deployment config for all kie servers (note that only the authoring templates will also include its exclusion by default):

          - name: MAVEN_MIRROR_OF 
            value: "external:*,!${APPLICATION_NAME}-rhpamcentr" 
          - name: RHPAMCENTR_MAVEN_REPO_ID 
            value: "${APPLICATION_NAME}-rhpamcentr"

The above only takes affect if a MAVEN_MIRROR_URL is specified, so this will not affect current behavior otherwise.