fix(db-mongodb): bug resolving joins when useJoinAggregations is disabled

[rubn-g]

What?

When using MongoDB adapter, with the option useJoinAggregations set to false, queries containing multiple joins were only executing the first join

When useJoinAggregations is disabled and a join includes multiple collections, only first was included.

For example, if we have this json query where (simplified real use case from the Folders feature), only the payload-folders join where processed.

{
  "or": [
    {
      "and": [
        {
          "relationTo": {
            "equals": "payload-folders"
          }
        }
      ]
    },
    {
      "and": [
        {
          "relationTo": {
            "equals": "media"
          }
        }
      ]
    }
  ]
}

Fixes

Go through multiple or and and operators in a query where, looking for the relationTo property, instead of keeping the first one found.