Promote squash commits

Related to https://gitlab.com/gitlab-org/gitlab-ee/issues/2624

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Design

Promote trial or license activation for regular EE on-prem sites.

Admin

• Having Start GitLab Enterprise Edition trial button.
• Having x on the top-right corner.
• Read more
• Link to the document, so users can know more about the feature.
• Link: https://docs.gitlab.com/ee/user/project/merge_requests/squash_and_merge.html
• Copy:

Improve Merge Requests with squash commit and GitLab Enterprise Edition.

Squashing lets you tidy up the commit history of a branch when accepting a merge request. 
It applies all of the changes in the merge request as a single commit, 
and then merges that commit using the merge method set for the project. [Read more]

Non-admin

• Copy:

Improve Merge Requests with squash commit and GitLab Enterprise Edition.

Squashing lets you tidy up the commit history of a branch when accepting a merge request. 
It applies all of the changes in the merge request as a single commit, 
and then merges that commit using the merge method set for the project. [Read more]

Contact your Administrator to upgrade your license.

Admin	Non-admin

For GitLab.com the feature promotion needs to go to purchase a GitLab.com plan

Admin

• Having Upgrade your plan button.
• Copy:

Upgrade your plan to activate Squach commit.

Squashing lets you tidy up the commit history of a branch when accepting a merge request. 
It applies all of the changes in the merge request as a single commit, 
and then merges that commit using the merge method set for the project. [Read more]

Non-admin

• Copy:

Upgrade your plan to activate Squach commit.

Squashing lets you tidy up the commit history of a branch when accepting a merge request. 
It applies all of the changes in the merge request as a single commit, 
and then merges that commit using the merge method set for the project. [Read more]

Contact your Administrator to upgrade your plan.

Admin	Non-admin