Add "project" filter option to group-level dependencies app

Why are we doing this work

In a previous iteration, we are adding the change that are needed to lay the ground for adding multiple filter-options to the table.

This issue captures the addition of a filter-by-project option:

Implementation Notes

• Add new token component (example: https://gitlab-org.gitlab.io/gitlab-ui/?path=/story/base-filtered-search--with-multi-select)
• Wire up with filter and search query (Vuex actions already available)
• Make sure that the changes are behind the group_level_licenses feature flag
• Add specs