[release/10.0] [QUIC] Disable Quic tests on AzL3 VM (#125817)

Backport of #125665 to release/10.0

## Customer Impact

- [ ] Customer reported
- [ ] Found internally

[Select one or both of the boxes. Describe how this issue impacts
customers, citing the expected and actual behaviors and scope of the
issue. If customer-reported, provide the issue number.]

## Regression

- [ ] Yes
- [ ] No

[If yes, specify when the regression was introduced. Provide the PR or
commit if known.]

## Testing

[How was the fix verified? How was the issue missed previously? What
tests were added?]

## Risk

[High/Medium/Low. Justify the indication by mentioning how risks were
measured and addressed.]

**IMPORTANT**: If this backport is for a servicing release, please
verify that:

- For .NET 8 and .NET 9: The PR target branch is `release/X.0-staging`,
not `release/X.0`.
- For .NET 10+: The PR target branch is `release/X.0` (no `-staging`
suffix).

## Package authoring no longer needed in .NET 9

**IMPORTANT**: Starting with .NET 9, you no longer need to edit a NuGet
package's csproj to enable building and bump the version.
Keep in mind that we still need package authoring in .NET 8 and older
versions.

---------

Co-authored-by: ManickaP <mapichov@microsoft.com>
Co-authored-by: Marie Píchová <11718369+ManickaP@users.noreply.github.com>

Author: github-actions[bot]

src/libraries/System.Net.Quic/tests/FunctionalTests/MsQuicPlatformDetectionTests.cs

@@ -9,6 +9,7 @@
 namespace System.Net.Quic.Tests
 {
     [Collection(nameof(QuicTestCollection))]
+    [ConditionalClass(typeof(QuicTestBase), nameof(QuicTestBase.IsNotAzureLinux3VM))]
     public class MsQuicPlatformDetectionTests : QuicTestBase
     {
         public MsQuicPlatformDetectionTests(ITestOutputHelper output) : base(output) { }