Fix parsing new line for literal style

[Łukasz Wroński]

in-yaml

certificate: |-
        -----BEGIN CERTIFICATE-----
        0MTk0MVoXDenkKThvP7IS9q
        +Dzv5hG392KWh5f8xJNs4LbZyl901MeReiLrPH3w=
        -----END CERTIFICATE----

Expected events:

+STR
+DOC
+MAP
=VAL :certificate
=VAL |-----BEGIN CERTIFICATE-----\n0MTk0MVoXDenkKThvP7IS9q\n+Dzv5hG392KWh5f8xJNs4LbZyl901MeReiLrPH3w=\n-----END CERTIFICATE----
-MAP
-DOC
-STR