Remove calls to load Mirrors in user.Dashboard (#20855) (#20897)

Backport #20855

Whilst looking at #20840 I noticed that the Mirrors data doesn't appear
to be being used therefore we can remove this and in fact none of the
related code is used elsewhere so it can also be removed.

Related #20840
Related #20804

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

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

Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

routers/web/user/home.go

@@ -100,39 +100,6 @@ func Dashboard(ctx *context.Context) {
 	}
 
 	var err error
-	var mirrors []*repo_model.Repository
-	if ctxUser.IsOrganization() {
-		var env organization.AccessibleReposEnvironment
-		if ctx.Org.Team != nil {
-			env = organization.OrgFromUser(ctxUser).AccessibleTeamReposEnv(ctx.Org.Team)
-		} else {
-			env, err = organization.AccessibleReposEnv(ctx, organization.OrgFromUser(ctxUser), ctx.Doer.ID)
-			if err != nil {
-				ctx.ServerError("AccessibleReposEnv", err)
-				return
-			}
-		}
-		mirrors, err = env.MirrorRepos()
-		if err != nil {
-			ctx.ServerError("env.MirrorRepos", err)
-			return
-		}
-	} else {
-		mirrors, err = repo_model.GetUserMirrorRepositories(ctxUser.ID)
-		if err != nil {
-			ctx.ServerError("GetUserMirrorRepositories", err)
-			return
-		}
-	}
-	ctx.Data["MaxShowRepoNum"] = setting.UI.User.RepoPagingNum
-
-	if err := repo_model.MirrorRepositoryList(mirrors).LoadAttributes(); err != nil {
-		ctx.ServerError("MirrorRepositoryList.LoadAttributes", err)
-		return
-	}
-	ctx.Data["MirrorCount"] = len(mirrors)
-	ctx.Data["Mirrors"] = mirrors
-
 	ctx.Data["Feeds"], err = models.GetFeeds(ctx, models.GetFeedsOptions{
 		RequestedUser:   ctxUser,
 		RequestedTeam:   ctx.Org.Team,