yaml-cpp: Bump release to 0.7.0

readonly ownership="yaml-cpp Upstream <robot@adios2>"

readonly subtree="thirdparty/yaml-cpp/yaml-cpp"

readonly repo="https://github.com/jbeder/yaml-cpp.git"

readonly tag="yaml-cpp-0.6.3"

readonly tag="yaml-cpp-0.7.0"

readonly shortlog="true"

readonly paths="

  LICENSE

  include/

  src/

"

extract_source () {