SOURCE_DATE_EPOCH specifies the timestamp, but needs to be rendered in
UTC timezone to ensure reproducible builds.
https://reproducible-builds.org/docs/source-date-epoch/
This is a follow-up to https://bugs.debian.org/978499 in apache fop,
as there is no way for fop itself to pass the timezone information for
some values.
Gbp-Pq: Name 0001-XMPSchemaAdapter.java-Use-UTC-timezone-when-SOURCE_D.patch
zhouganqing