Improve link times on Windows by using LLD for linking
Currently the Windows CI builds are typically lasting over 3 hours. The primary cause of this appears to be poor performance in `ld.bfd`, especially when linking testsuite tests.
One option to fix this is to try using LLD for linking. Unfortunately the msys2 `gcc` does not support `-fuse-ld=lld`.
<details><summary>Trac metadata</summary>
| Trac field | Value |
| ---------------------- | ------------ |
| Version | 8.6.3 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | high |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture | |
</details>
<!-- {"blocked_by":[],"summary":"Improve link times on Windows","status":"New","operating_system":"","component":"Compiler","related":[],"milestone":"","resolution":"Unresolved","owner":{"tag":"Unowned"},"version":"8.6.3","keywords":[],"differentials":[],"test_case":"","architecture":"","cc":[""],"type":"Bug","description":"Currently the Windows CI builds are typically lasting over 3 hours. The primary cause of this appears to be poor performance in `ld.bfd`, especially when linking testsuite tests.\r\n\r\nOne option to fix this is to try using LLD for linking. Unfortunately the msys2 `gcc` does not support `-fuse-ld=lld`.","type_of_failure":"OtherFailure","blocking":[]} -->
issue