Add "Invite a group" feature to invite members modal [RUN ALL RSPEC]

What does this MR do?

• Adds support to the InviteMembersModal component so it can be used to select a group to invite, similar to how it works for "existing member or email" search.

• Adds a new trigger to the Members page to replace the old "Invite Group" form.

Background

• This feature is all behind a feature flag invite_members_group_modal

• The "Invite a group" modal works the same way as the old form which is documented here: https://docs.gitlab.com/ee/user/project/members/share_project_with_groups.html

• Related to Issue https://gitlab.com/gitlab-org/gitlab/-/issues/223183

• Related to Merge Request !49615 (merged)

• Related to https://gitlab.com/gitlab-org/gitlab/-/issues/297581

Screenshots (strongly suggested)

Invite members	Invite a group

Members page before	Members page after

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