Remove obsolete change of email on profile page (#13341)

* Remove obsolete change of email on profile page

The change email on the account profile page is out-of-date
and unnecessary.

Changing email should be done using the account page.

Fix #13336

Signed-off-by: Andrew Thornton <art27@cantab.net>

modules/auth/user_form.go

@@ -199,7 +199,6 @@ func (f *AccessTokenForm) Validate(ctx *macaron.Context, errs binding.Errors) bi
 type UpdateProfileForm struct {
 	Name                string `binding:"AlphaDashDot;MaxSize(40)"`
 	FullName            string `binding:"MaxSize(100)"`
-	Email               string `binding:"Required;Email;MaxSize(254)"`
 	KeepEmailPrivate    bool
 	Website             string `binding:"ValidUrl;MaxSize(255)"`
 	Location            string `binding:"MaxSize(50)"`