serialization: Use ‘bytevector-slice’ from Guile >= 3.0.9.

* guix/serialization.scm (sub-bytevector): Remove.
(read-byte-string): Use ‘bytevector-slice’.
* configure.ac: Require Guile 3.0.9.
* doc/contributing.texi (Requirements): Adjust accordingly.

Change-Id: I7aa11a2182530ea5131be591db03b17efb6847a4
Signed-off-by: Ludovic Courtès <ludo@gnu.org>
Merges: #4495

1 files changed, 1 insertions, 1 deletions

diff --git a/doc/contributing.texi b/doc/contributing.texi
index c0a426db8af..06b4883baa2 100644
--- a/doc/contributing.texi
+++ b/doc/contributing.texi
@@ -66,7 +66,7 @@ GNU Guix depends on the following packages:
 
 @itemize
 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
-version 3.0.3 or later;
+version 3.0.9 or later;
 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
 0.1.0 or later;
 @item