Disable failing DNS tests on SLES

[ViktorHofer]

As there's currently no infrastructure to disable just for SLES,
disabling for its parent, which is Linux.

#48751

cc @dotnet/ncl

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Issue Details

---

As there's currently no infrastructure to disable just for SLES,
disabling for its parent, which is Linux.

#48751

cc @dotnet/ncl

Author:	ViktorHofer
Assignees:	-
Labels:	area-System.Net
Milestone:	-

[stephentoub]

As there's currently no infrastructure to disable just for SLES, disabling for its parent, which is Linux.

We can't add an IsSles like we do for other distros?

runtime/src/libraries/Common/tests/TestUtilities/System/PlatformDetection.Unix.cs

Lines 17 to 31 in 2be64db

	private static bool IsLinux => RuntimeInformation.IsOSPlatform(OSPlatform.Linux);
	public static bool IsOpenSUSE => IsDistroAndVersion("opensuse");
	public static bool IsUbuntu => IsDistroAndVersion("ubuntu");
	public static bool IsDebian => IsDistroAndVersion("debian");
	public static bool IsAlpine => IsDistroAndVersion("alpine");
	public static bool IsDebian8 => IsDistroAndVersion("debian", 8);
	public static bool IsDebian10 => IsDistroAndVersion("debian", 10);
	public static bool IsUbuntu1604 => IsDistroAndVersion("ubuntu", 16, 4);
	public static bool IsUbuntu1704 => IsDistroAndVersion("ubuntu", 17, 4);
	public static bool IsUbuntu1710 => IsDistroAndVersion("ubuntu", 17, 10);
	public static bool IsUbuntu1710OrHigher => IsDistroAndVersionOrHigher("ubuntu", 17, 10);
	public static bool IsUbuntu1804 => IsDistroAndVersion("ubuntu", 18, 04);
	public static bool IsUbuntu1810OrHigher => IsDistroAndVersionOrHigher("ubuntu", 18, 10);
	public static bool IsTizen => IsDistroAndVersion("tizen");
	public static bool IsFedora => IsDistroAndVersion("fedora");

[ViktorHofer]

Feel free to update the PR with your suggestion. I'm on the phone and won't have access to my PC the next few hours.

[ViktorHofer]

With infrastructure I meant the platform detection in XUnitExtensions so that it can be applied to an ActiveIssueAttribute.

[ViktorHofer]

Can someone please approve? The failures are showing up on every PR that runs these tests (on SLES).

[wfurt]

looks ok for the emergency.
I will follow-up on this separately.