"Membership Request" link is duplicate on group menu

Problem/Motivation

The "Membership request" link is duplicate on group menu.

Steps to reproduce

• Enable Social Group Request module
• Create a group
• Check link menu from group create before

Proposed resolution

The Social Group Request module extend some features from GRequest module and it is adding a link menu for "Membership request" page.
So add a validation to remove link-menu from GRequest module and use from Social Group Request module.

Remaining tasks

N/A

User interface changes

N/A

API changes

N/A

Data model changes

N/A