gnu: glibc: Don't use full version string in locale path.
This is a follow-up to commit
ee3ebf1a357bd4eb36a2fa1790a7b549cffb305a.
Fixes <https://bugs.gnu.org/29537>.
* gnu/packages/base.scm (glibc/linux)[version]: Change to
2.26.91-gaaa2eb83b8.
[source](uri): Adjust accordingly.
[arguments]: Use VERSION-MAJOR+MINOR for locales path.
(glibc-locales, glibc-utf8-locales): Likewise.
* guix/packages.scm (patch-and-repack): Likewise.
* guix/profiles.scm (ca-certificate-bundle, profile-derivation): Likewise.