Update using-custom-rewrite-providers-with-url-rewrite-module.md

[r-V3]

The download link is invalid. Deleted it.

Third part saved download link: https://web.archive.org/web/20200801000000id_/download.microsoft.com/download/3/9/E/39E30671-7AD2-4902-B56B-C300D862595E/RewriteExtensibility.msi

The URL Rewrite Extensibility Samples related docs:

1. https://learn.microsoft.com/en-us/iis/extensions/url-rewrite-module/using-url-rewrite-module-20#installing-the-extensibility-samples
2. https://iis-umbraco.azurewebsites.net/downloads/microsoft/url-rewrite

Please check if there is an official download way.

[wadepickett]

Approved with link suggestion change.

[wadepickett]

Re:
I think it would be better to point the the IIS URL Rewrite 2.1 download page which has valid download links for that >> version, rather than to instruct to install the URL Rewrite Extensibility Samples for 2.0 but not have a link to point them to. >> From what I can discover it looks like those were indeed removed and the 2.1 module is now pointed to instead in some cases.

We can't use the installer copy from the way back machine you pointed to, but thanks for providing the link.

@John-Hart, do you have a different preference for this situation, or happen to know if the URL Rewrite 2.1 samples are still available somewhere. I could not find it.
I did find this public Q&A 2021 note from Sam Wu here:
https://learn.microsoft.com/en-us/answers/questions/438658/link-broken-for-rewriteextensibility-msi-for-url-r

@John-Hart, since this solution follows generally what Sam Wu on the team suggested earlier I will go head and commit and squash. If there is a different preference, let me know and I will change to what you need.

[wadepickett]

Also tracked with and fixes dotnet/AspNetCore.Docs#33954

[wadepickett]

Thanks @r-V3!