Remove `IsEmpty` workaround in `Span` and `ReadOnlySpan`

[deeprobin]

Follow up issue for #10950

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this could be labeled as easy btw

---

As described in #63902, it would be good to remove comments and workarounds that have already been fixed.

So these workarounds may be replaced by the non-workaround-way:

runtime/src/libraries/System.Private.CoreLib/src/System/Span.cs

Lines 155 to 162 in f04a242

	/// <summary>
	/// Returns true if Length is 0.
	/// </summary>
	public bool IsEmpty
	{
	[NonVersionable]
	get => 0 >= (uint)_length; // Workaround for https://github.com/dotnet/runtime/issues/10950
	}

runtime/src/libraries/System.Private.CoreLib/src/System/ReadOnlySpan.cs

Lines 150 to 157 in f04a242

	/// <summary>
	/// Returns true if Length is 0.
	/// </summary>
	public bool IsEmpty
	{
	[NonVersionable]
	get => 0 >= (uint)_length; // Workaround for https://github.com/dotnet/runtime/issues/10950
	}

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Issue Details

---

Follow up issue for #10950

---

As described in #63902, it would be good to remove comments and workarounds that have already been fixed.

So these workarounds may be replaced by the non-workaround-way:

runtime/src/libraries/System.Private.CoreLib/src/System/Span.cs

Lines 155 to 162 in f04a242

	/// <summary>
	/// Returns true if Length is 0.
	/// </summary>
	public bool IsEmpty
	{
	[NonVersionable]
	get => 0 >= (uint)_length; // Workaround for https://github.com/dotnet/runtime/issues/10950
	}

runtime/src/libraries/System.Private.CoreLib/src/System/ReadOnlySpan.cs

Lines 150 to 157 in f04a242

	/// <summary>
	/// Returns true if Length is 0.
	/// </summary>
	public bool IsEmpty
	{
	[NonVersionable]
	get => 0 >= (uint)_length; // Workaround for https://github.com/dotnet/runtime/issues/10950
	}

Author:	deeprobin
Assignees:	-
Labels:	area-System.Runtime, untriaged
Milestone:	-