Update the logic of a record.Key formatting

[voscob]

Description

I've changed the logic of a record.Key formatting.

The keyColumns is an optional field.
If the field is not empty the system uses it to format record.Key, if not - makes a request to the database and uses the
received list of primary keys of the specified table. If the table does not contain primary keys, the system uses the
value of the orderingColumn field as the keyColumns value.

Quick checks:

• I have followed the Code Guidelines.
• There is no other pull request for the same update/change.
• I have written unit tests.
• I have made sure that the PR is of reasonable size and can be easily reviewed.