Update robots.txt to exclude group_members and project_members, which can...

Update robots.txt to exclude group_members and project_members, which can expose sensitive user information to the web. Please see https://developers.google.com/search/reference/robots_txt for the correct wildcard format. 

public/robots.txt

@@ -70,3 +70,5 @@ Disallow: /*/*/hooks
 Disallow: /*/*/services
 Disallow: /*/*/protected_branches
 Disallow: /*/*/uploads/
+Disallow: /*/-/group_members
+Disallow: /*/project_members