Remove stale Microsoft.Extensions.FileSystemGlobbing binding redirect from testhost.x86 and datacollector

[Amaury Levé (Evangelink)]

What

Remove the stale Microsoft.Extensions.FileSystemGlobbing <bindingRedirect> from src/testhost.x86/app.config and src/datacollector/app.config. The redirect is kept in src/vstest.console/app.config (the only EXE that legitimately ships and uses the assembly, via FilePatternParser).

Why

Neither testhost.x86.exe nor datacollector.exe references Microsoft.Extensions.FileSystemGlobbing, and the DLL doesn't ship beside them in the Microsoft.TestPlatform.CLI nupkg's contentFiles/any/net10.0/TestHostNetFramework/ folder. A binding redirect pointing to a DLL that isn't on the probing path is the same anti-pattern fixed for System.Diagnostics.DiagnosticSource in #15776 (root cause of #15765 — MissingMethodException on net462 with DisableAppDomain=true).

How it was discovered

This is the latent issue the hardened verifier from #15778 catches. The failure currently surfaces only on the rel/18.6 VMR build:

1. Microsoft.TestPlatform.csproj gates IsPackable on '$(DotNetBuild)' != 'true' (the package "relies on a VS license"), so in VMR mode it isn't produced. That nupkg is the one that ships testhost.x86.exe/datacollector.exe in tools/net462/Common7/IDE/Extensions/TestPlatform/ with Microsoft.Extensions.FileSystemGlobbing.dll right next to them — which is what masks the stale redirect in vstest's normal pipeline (Find-ExeInPackages prefers non-TestHostNetFramework layouts).
2. Once that layout disappears, the verifier only finds the EXEs inside Microsoft.TestPlatform.CLI's TestHostNetFramework/ folder, where the DLL isn't shipped → error.
3. The DotNetBuild != 'true' skip on _VerifyNuGetPackages (commit 37087fc) is on main and rel/18.8 but not backported to rel/18.6 or rel/18.7, so the verifier still runs in the VMR pack on those branches.

This PR fixes the underlying issue. It should be cherry-picked to rel/18.6 (where it actively unblocks the VMR build) and rel/18.7 for consistency.

[Copilot]

Pull request overview

Removes a stale Microsoft.Extensions.FileSystemGlobbing binding redirect from the .NET Framework testhost.x86 and datacollector app.configs, aligning binding redirects with the assemblies these executables actually ship alongside and preventing validation failures when the target DLL is absent.

Changes:

• Removed Microsoft.Extensions.FileSystemGlobbing <dependentAssembly> binding redirects from src/testhost.x86/app.config and src/datacollector/app.config.
• Kept vstest.console behavior unchanged (no redirect removal there in this PR).

Show a summary per file

File	Description
src/testhost.x86/app.config	Drops the stale Microsoft.Extensions.FileSystemGlobbing bindingRedirect from testhost.x86 configuration.
src/datacollector/app.config	Drops the stale Microsoft.Extensions.FileSystemGlobbing bindingRedirect from datacollector configuration.

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 0