R1:8cc6fe465c53

Fix diffusion.branchquery returning dictionary instead of array when branches are filtered out

Summary:
`diffusion.branchquery` can return dictionary instead of array if some branches are filtered out.
Eg.:
```
{
"result": [
{
"shortName": "master",
"commitIdentifier": "2817b0d8f79748ddfad0220c46d9b20bea34f460",
"refType": "branch",
"rawFields": {
"objectname": "2817b0d8f79748ddfad0220c46d9b20bea34f460",
"objecttype": "commit",
```
might become:
```
{…