(#452): Implement SvgHandle::has_element_with_id()

This is analogous to rsvg_handle_has_sub().

Fixes #452
7 jobs for master in 35 minutes and 46 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
passed #330081
fedora test

00:08:51

 
  Lint
manual #330083
allowed to fail manual
clippy
manual #330082
allowed to fail manual
rustfmt
passed #330084
tarball

00:10:07

 
  Cross Distro
passed #330087
debian_i386:testing

00:16:46

passed #330086
allowed to fail
debian:testing

00:07:57

failed #330085
allowed to fail
fedora:rawhide

00:06:28

 
Name Stage Failure
failed
fedora:rawhide Cross Distro
make[2]: Leaving directory '/builds/GNOME/librsvg/_build/tests'
make[1]: *** [Makefile:1414: check-recursive] Error 1
make[1]: Leaving directory '/builds/GNOME/librsvg/_build'
make: *** [Makefile:1710: check] Error 2
Uploading artifacts...
_build/tests/*.log: found 9 matching files
_build/tests/output/: found 743 matching files
Uploading artifacts to coordinator... ok id=330085 responseStatus=201 Created token=sKdeSgKx
ERROR: Job failed: exit code 1