branch core-updates updated (8027711 -> 0715793)

[guix-commits]

apteryx pushed a change to branch core-updates
in repository guix.

    from 8027711  gnu: tzdata-for-tests: Update to 2020d.
     new 485ac28  utils: Allow text substitution even in the presence of NUL 
characters.
     new 0715793  build-systems/emacs: No longer skip patching of files 
containing NULs.

The 2 revisions listed above as "new" are entirely new to this
repository and will be described in separate emails.  The revisions
listed as "add" were already present in the repository and have only
been added to this reference.


Summary of changes:
 guix/build/emacs-build-system.scm | 16 +----------
 guix/build/utils.scm              | 57 +++++++++++++++++++++++++++++++--------
 tests/build-utils.scm             | 24 ++++++++++++++++-
 3 files changed, 70 insertions(+), 27 deletions(-)