Fix relation between standard objects

[Weiko]

This PR fixes a few issues

• The FE code was sending a viewId to a view property instead of viewId during viewField creation (after relation creation). Note: this part should be moved to the BE.
• The toDescription field is optional, when a description was missing we were concatenating it to format the relation description and it was containing undefined, now we don't try to create a description if none is provided.
• Fixes the targetColumnMap not defined when we were creating relations to standard objects. In the backend we run the query against pg_graphql with a fieldAlias however if the field is custom and targetColumnMap is empty we query it with undefined like this bar: undefined (see RelationFieldAliasFactory). The alias is actually redundant here it seems so maybe there are things we can improve 🤔 (cc @magrinj)

[charlesBochet]

Let's also fix opportunity.person (should be nullable) and note.author (should be prefilled by the FE for now)