Don't return duplicated users who can create org repo (#22560) (#22562)

- Backport of #22560
- Currently the function `GetUsersWhoCanCreateOrgRepo` uses a query that
is able to have duplicated users in the result, this is can happen under
the condition that a user is in team that either is the owner team or
has permission to create organization repositories.
- Add test code to simulate the above condition for user 3,
[`TestGetUsersWhoCanCreateOrgRepo`](a1fcb1cfb8/models/organization/org_test.go (L435))
is the test function that tests for this.
  - The fix is quite trivial, use a map as a set to get distinct orgs.

models/organization/org_test.go

@@ -92,11 +92,12 @@ func TestUser_GetTeams(t *testing.T) {
 	org := unittest.AssertExistsAndLoadBean(t, &organization.Organization{ID: 3})
 	teams, err := org.LoadTeams()
 	assert.NoError(t, err)
-	if assert.Len(t, teams, 4) {
+	if assert.Len(t, teams, 5) {
 		assert.Equal(t, int64(1), teams[0].ID)
 		assert.Equal(t, int64(2), teams[1].ID)
 		assert.Equal(t, int64(12), teams[2].ID)
-		assert.Equal(t, int64(7), teams[3].ID)
+		assert.Equal(t, int64(14), teams[3].ID)
+		assert.Equal(t, int64(7), teams[4].ID)
 	}
 }
 
@@ -293,7 +294,7 @@ func TestUser_GetUserTeamIDs(t *testing.T) {
 		assert.NoError(t, err)
 		assert.Equal(t, expected, teamIDs)
 	}
-	testSuccess(2, []int64{1, 2})
+	testSuccess(2, []int64{1, 2, 14})
 	testSuccess(4, []int64{2})
 	testSuccess(unittest.NonexistentID, []int64{})
 }
@@ -448,7 +449,7 @@ func TestGetUsersWhoCanCreateOrgRepo(t *testing.T) {
 	users, err = organization.GetUsersWhoCanCreateOrgRepo(db.DefaultContext, 7)
 	assert.NoError(t, err)
 	assert.Len(t, users, 1)
-	assert.EqualValues(t, 5, users[0].ID)
+	assert.NotNil(t, users[5])
 }
 
 func TestUser_RemoveOrgRepo(t *testing.T) {