deepmerge in defaultSchmea merge function

[Malo Guertin]

In defaultSchema merge function you have:

const merged = merge({}, this, ...schemas)

is there a reason for using lodash' deepMerge instead of a simple reduce:

const merged = schemas.reduce((merged, schema) => ({...merged, ...schema}), this)

Using lodash merge makes it incredibly slow with a lot of refs to other schemas and even worse if you want to use self referencing