Update link to ASP.NET Core tools

[svick]

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[dotnet-policy-service]

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[Copilot]

Pull request overview

This PR updates a stale documentation link in the ASP.NET Core tools documentation. The original link pointed to the now-archived aspnet/DotNetTools GitHub repository, which has since been merged into the dotnet/aspnetcore monorepo. The updated link points to the correct current location of the tools source.

Changes:

• Updated the "For more information" link in aspnetcore-tools.md from the archived aspnet/DotNetTools repo to the active dotnet/aspnetcore/tree/main/src/Tools path.