License Compliance page: Remove policy violation banner, add pill, and update description

Description

New issue created to discuss UX problems mentioned in !74143 (comment 734021746).

Is this alert needed? I'm guessing this is to explain the violation shown in the table below it?:

Changes

1. Remove the warning alert at the top of the page

2. Change the page description when default tab is shown

from:

Displays licenses detected in the project, based on the latest successful scan • 3 months ago

to:

Displays licenses detected in the project that are out of compliance with the project's policies, based on the latest successful scan • 3 months ago

3. Add a pill/ badge counter to the default tab

Implementation Plan for Second Proposal

1. Remove gl-alert component from https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/license_compliance/components/app.vue#L106

2. In https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/license_compliance/components/app.vue#L134 re-use hasViolations mappedGetter to conditionally provide warning badge variant prop.

3. Update text copy in https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/app/assets/javascripts/license_compliance/components/pipeline_info.vue#L29

See:

https://gitlab.com/gitlab-org/gitlab-ui/-/blob/main/src/utils/constants.js#L33

https://gitlab.com/gitlab-org/gitlab-ui/-/blob/main/src/components/base/badge/badge.vue#L27

1. Update unit tests