This fixes a pesky failure in vs2019 vc2019x64ninja for d/11 dub:
```
Searching in DUB cache for compatible urld.lib
WARNING: No such cache folder: C:\Users\VssAdministrator\AppData\Local\dub\packages\urld-2.1.1\urld\.dub\build
ERROR: urld@2.1.1 not found
You may try the following command to install the necessary DUB libraries:
dub run --yes dub-build-deep -- urld --arch=x86_64 --compiler=dmd --build=debug
Run-time dependency urld found: NO
test cases\d\11 dub\meson.build:13:11: ERROR: Dependency "urld" not found
```
Follow dub's advice by installing urld in ci/run.ps1 before the testsuite;
we were already doing this for ubuntu, opensuse, and even recommending
it in our docs before now:
* ci/ciimage/ubuntu-rolling/install.sh
* ci/ciimage/opensuse/install.sh
* docs/markdown/Dependencies.md
We also bump to 'ci4' which has newer D added (from the cidata repo).