#indifferent! does not seem to return an hash that works with #fetch

[victormartins]

Using HashKit v0.6.0

helper =  HashKit::Helper.new 
=> #<HashKit::Helper:0x000055cbd1f70498>
h = {foo: 1}
=> {:foo=>1}

helper.indifferent!(h)
=> {:foo=>1}

# Works with direct access
h['foo']
=> 1

# Fails using #fetch
h.fetch('foo')
KeyError: key not found: "foo"