Move project members into tabs

What does this MR do?

Related to #281824 (closed)

This is the first step in giving the project members view the same treatment that was given to the group members view in &4233 (closed).

This MR reorganizes the project members into tabs. We are not using the GitLab UI tabs yet, but we are planning on migrating to those once the Vue app is all setup. The reason for this being that the group members view is not yet using the GitLab UI tabs either so it will be easier to migrate both of the views at the same time since they use shared Vue components.

Screenshots (strongly suggested)

Desktop

Page	Before	After
Members tab
Groups tab	N/A
Invites tab	N/A
Access requests tab	N/A

Mobile

Page	Before	After
Members tab
Groups tab	N/A
Invites tab	N/A
Access requests tab	N/A

Local testing

1. Create a project
2. Navigate to Project -> Members

How to add a group

1. Navigate to Project -> Members
2. Click the Invite group tab

How to add an invited member

1. Navigate to Project -> Members
2. In the GitLab member or Email address enter an email that a user does not already own
3. Click Invite "example@test.com" by email

How to request access to a project

1. Log in (or impersonate) a user that doesn't already have access to the group
2. Navigate to the project overview
3. Click Request access located below the project name

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team