Sizes of node in network graph do not work with relations

[canasdiaz]

Kibana version:

Kibana 6.8.6 (the one currently used for biterg.io instances)

Elasticsearch version:

N/A

Server OS version:

N/A

Browser version:

Firefox 91.12.0esr (64-bit)

Browser OS version:

Linux 64-bit

Original install method (e.g. download page, yum, from source, etc.):

Debian package

Description of the problem including expected versus actual behavior:

When creating a network graph with different node sizes, they all are the same size as soon as you add a Relation.

Steps to reproduce:

1. Go to chaoss.biterg.io
2. Create a network graph on the index github2_pull_requests
3. Set Node Size (unique count of issue_url) and a node (terms / author_org_name)
4. Display the chart and watch the node size
5. Set a Relation (terms / issue_url)
6. The size of the nodes is equal while it shouldn't

Errors in browser console (if relevant):

N/A

Provide logs and/or server output (if relevant):

N/A