BUG pre-aggregation not selected on many-to-many relationship + measure

**Problem**
I am running into a problem with pre-aggregations
I have three tables from postgresql :

- client, client_agency, agency
- client and agency have a many to many relationship through client_agency
- the cubes have no measures, only dimensions

I have one table from bigQuery :

- report
- report has client id, and a many to one relationship with client
- report has many measures (all of type SUM)
- a pre aggregation (type : rollup_join, external : true) has been defined containing dimensions from client, client_agency, agency and report, as well as the report measures

DATA MODEL:
```
cube("client", {
sql: `SELECT * FROM "s_db".clients`,
dataSource: "pg",
dimensions: {
id: {
sql: "id",
type: "number",
primaryKey: true,
},
name: {
sql: "name",
type: "string",
},
updated_at: {
sql: "updated_at",
type: "time",
},
},
joins: {
client_agency: {
sql: `${CUBE.id} = ${client_agency.client_id}`,
relationship: `many_to_one`,
},
},
pre_aggregations: {
main: {
type: `rollup`,
external: true,
dimensions: [CUBE.id, CUBE.name, CUBE.updated_at],
refresh_key: {
every: `1 day`,
sql: `SELECT MAX(updated_at) FROM "s_db".clients`,
},
indexes: {
client_id: {
columns: [CUBE.id],
},
},
},
},
});

cube("agency", {
sql: `SELECT * FROM "s_db".agencies`,
dataSource: "pg",
dimensions: {
id: {
sql: "id",
type: "number",
primaryKey: true,
},
name: {
sql: "name",
type: "string",
},
updated_at: {
sql: "updated_at",
type: "time",
},
},
joins: {
client_agency: {
sql: `${CUBE.id} = ${client_agency.agency_id}`,
relationship: `many_to_one`,
},
},
pre_aggregations: {
main: {
type: `rollup`,
external: true,
dimensions: [CUBE.id, CUBE.name],
refresh_key: {
every: `1 day`,
sql: `SELECT MAX(updated_at) FROM "s_db".agencies`,
},
indexes: {
agency_id: {
columns: [CUBE.id],
},
},
},
},
});

cube("client_agency", {
sql: `SELECT * FROM "s_db".client_agency`,
dataSource: "pg",
dimensions: {
agency_id: {
sql: "agency_id",
type: "number",
primaryKey: true,
},
client_id: {
sql: "client_id",
type: "number",
primaryKey: true,
},
},
joins: {
agency: {
sql: `${CUBE.agency_id} = ${agency.id}`,
relationship: `one_to_many`,
},
client: {
sql: `${CUBE.client_id} = ${client.id}`,
relationship: `one_to_many`,
},
},
pre_aggregations: {
main: {
type: `rollup`,
external: true,
dimensions: [
CUBE.agency_id,
CUBE.client_id
],
measures: [CUBE.count],
refresh_key: {
every: `1 day`,
},
indexes: {
agency_id: {
columns: [CUBE.agency_id],
},
client_id: {
columns: [CUBE.client_id],
},
},
},
},
});
cube("report", {
title: "Report",
name: "report",
sql: "SELECT * FROM reports.report",
dataSource: "bq",
dimensions: {
date: {
sql: "CAST(Date as TIMESTAMP)",
type: "time",
primaryKey: false,
shown: true,
},
account_id: {
sql: "account_id",
type: "string",
primaryKey: true,
shown: true,
},
client_id: {
sql: "client_id",
type: "string",
primaryKey: true,
shown: true,
},
updated_at: {
sql: "updated_at",
type: "time",
primaryKey: false,
shown: true,
},
},
measures: {
impressions: {
sql: "impressions",
type: "sum",
},
clicks: {
sql: "clicks",
type: "sum",
},
},
joins: {
client: {
sql: `${CUBE.client_id} = ${client.id}`,
relationship: "many_to_one",
},
},
pre_aggregations: {
main: {
type: "rollup",
external: true,
dimensions: [CUBE.date, CUBE.account_id, CUBE.client_id, CUBE.updated_at],
measures: [CUBE.impressions, CUBE.clicks],
time_dimension: CUBE.date,
granularity: "day",
partition_granularity: "month",
refresh_key: {
every: "1 minute",
sql: `SELECT MAX(updated_at) FROM (SELECT * FROM reports.report) AS report WHERE ${FILTER_PARAMS.report.date.filter(
"CAST(Date AS TIMESTAMP)"
)}`,
},
indexes: {
client_id: {
columns: [CUBE.client_id],
},
},
},
report_client_client_agency_agency:
{
type: `rollup_join`,
external: true,
time_dimension: CUBE.date,
granularity: `day`,
dimensions: [
CUBE.date,
CUBE.account_id,
CUBE.client_id,
CUBE.updated_at,
client.id,
client.name,
client.updated_at,
client_agency.agency_id,
client_agency.client_id,
agency.id,
agency.name,
agency.updated_at,
],
measures: [
CUBE.impressions,
CUBE.clicks
],
rollups: [
CUBE.main,
client.main,
client_agency.main,
agency.main,
],
},
},
rewriteQueries: false,
});
```

The problem:

1. If I make a query with dimensions from all 4 tables (no measures), the pre aggreagation is selected (the result is correct)
2. If I make a query with one measure from report and dimensions from client, the pre aggregation is selected (the result is correct)
3. If I make a query with one measure from report and dimensions from client AND AGENCY, the pre aggregation is NOT selected, I get the following error:

**To join across data sources use rollupJoin with Cube Store. If rollupJoin is defined, this error indicates it doesn't match the query. Please use Rollup Designer to verify it's definition. Found data sources: bq, p**g

Problematic query:
```
{
"order": {
"report.date": "asc"
},
"dimensions": [
"report.account_id",
"agency.name",
"client.name"
],
"measures": [
"report.clicks"
]
}
```

But if I use Rollup Designer it tells me to add the metric to the pre-aggregation, just like I already have.