fix: support YAML custom tags

[pacha]

This PR provides support for custom tags (ie. foo: !example bar) in YAML:

# input
foo:
  bar: !one_tag
  - one
  - two
  baz: !other_tag
  - spam
  - eggs
  bat: !even_one_more_tag
  - this
  - that

# patch
foo:
  baz:
  - four
  - five
  bat: !new_tag
  - six
  - seven

# output
foo:
  bar: !one_tag
  - one
  - two
  baz:
  - four
  - five
  bat: !new_tag
  - six
  - seven