Added node label in the tree end point response

[waychal]

Added missing node label in the response of rest api tree endpoint.

[ltalirz]

Could you perhaps add one test?
Or is accessing the nodelabel already tested?

[coveralls]

Coverage increased (+0.006%) to 56.049% when pulling f111f2d on waychal:tree_endpoint into c6426c0 on aiidateam:release_v0.12.3.

[waychal]

@ltalirz there is test available for tree endpoint. We do not specifically check the information passed for every node or edge.

[ltalirz]

We do not specifically check the information passed for every node or edge.

Perhaps we could change this situation? ;-)

Does not have to be entirely exhaustive but checking at least once for each key that the expected value is returned would seem reasonable, no?

[waychal]

I have updated the test where the important attributes displayed for node in front end are checked in response json data.

[ltalirz]

Thanks!