internal/rule: make squashedTable sql.Node instead of sql.Table
internal/rule: make squashedTable sql.Node instead of sql.Table

If a node is a sql.Table, it's enforced using a validation rule that all fields in the schema must have as the source the name of the table. To bypass that validation, we need to make squashedTable a sql.Node instead.

Signed-off-by: Miguel Molina <75004f149038473757da0be07ef76dd4a9bdbc8d@erizocosmi.co>

gitql/gitql,gitql/gitql