gnu: services: Revert to deleting and updating all matching services

This patch reverts the behavior introduced in
181951207339508789b28ba7cb914f983319920f which caused ‘modify-services’
clauses to only match a single instance of a service.

We will now match all service instances when doing a deletion or update, while
still raising an exception when trying to match against a service that does
not exist in the services list, or which was deleted explicitly by a ‘delete’
clause (or an update clause that returns ‘#f’ for the service).

Fixes: #64106

* gnu/services.scm (%modify-services): New procedure.
(modify-services): Use it.
(apply-clauses): Add DELETED-SERVICES argument, change to modify one service
at a time.
* tests/services.scm
("modify-services: delete then modify")
("modify-services: modify then delete")
("modify-services: delete multiple services of the same type")
("modify-services: modify multiple services of the same type"): New tests.

Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Modified-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>

build: Add missing guix-gc.timer file to binary tarball.

Partially fixes <https://issues.guix.gnu.org/65117>.

* nix/local.mk (nodist_systemdservice_DATA): Add etc/guix-gc.timer.

gnu: texlive-tpslifonts: Remove duplicate definition.

* gnu/packages/tex.scm (texlive-texmate): Remove duplicate variable.

gnu: texlive-isodate: Remove duplicate definition.

* gnu/packages/tex.scm (texlive-isodate): Remove duplicate variable.

gnu: texlive-glossaries-extra: Remove duplicate definition.

* gnu/packages/tex.scm (texlive-glossaries-extra): Remove duplicate
definition.

gnu: Add texlive-scheme-full.

* gnu/packages/tex.scm (texlive-scheme-full): New variable.

gnu: Add texlive-collection-latexextra.

* gnu/packages/tex.scm (texlive-collection-latexextra): New variable.

gnu: Add texlive-zwpagelayout.

* gnu/packages/tex.scm (texlive-zwpagelayout): New variable.

gnu: Add texlive-zwgetfdate.

* gnu/packages/tex.scm (texlive-zwgetfdate): New variable.

gnu: Add texlive-zref-vario.

* gnu/packages/tex.scm (texlive-zref-vario): New variable.

gnu: Add texlive-zref-clever.

* gnu/packages/tex.scm (texlive-zref-clever): New variable.

gnu: Add texlive-zref-check.

* gnu/packages/tex.scm (texlive-zref-check): New variable.

gnu: Add texlive-ziffer.

* gnu/packages/tex.scm (texlive-ziffer): New variable.

gnu: Add texlive-zennote.

* gnu/packages/tex.scm (texlive-zennote): New variable.

gnu: Add texlive-zed-csp.

* gnu/packages/tex.scm (texlive-zed-csp): New variable.

gnu: Add texlive-zebra-goodies.

* gnu/packages/tex.scm (texlive-zebra-goodies): New variable.

gnu: Add texlive-yplan.

* gnu/packages/tex.scm (texlive-yplan): New variable.

gnu: Add texlive-ycbook.

* gnu/packages/tex.scm (texlive-ycbook): New variable.

gnu: Add texlive-yaletter.

* gnu/packages/tex.scm (texlive-yaletter): New variable.

gnu: Add texlive-yagusylo.

* gnu/packages/tex.scm (texlive-yagusylo): New variable.