refactor: remove zombie Span.Replace

Author: oliverbooth

X10D/src/Collections/SpanExtensions.cs

@@ -16,28 +16,6 @@ public static ReadOnlySpan<T> AsReadOnly<T>(this in Span<T> source)
         return source;
     }
 
-#if !NET8_0_OR_GREATER
-    /// <summary>
-    ///     Replaces all occurrences of a specified element in a span of elements with another specified element.
-    /// </summary>
-    /// <param name="haystack">The source span.</param>
-    /// <param name="needle">The element to replace.</param>
-    /// <param name="replacement">The replacement element.</param>
-    /// <typeparam name="T">The type of elements in <paramref name="haystack" />.</typeparam>
-    public static void Replace<T>(this Span<T> haystack, T needle, T replacement) where T : struct
-    {
-        var comparer = EqualityComparer<T>.Default;
-
-        for (var index = 0; index < haystack.Length; index++)
-        {
-            if (comparer.Equals(haystack[index], needle))
-            {
-                haystack[index] = replacement;
-            }
-        }
-    }
-#endif
-
 #if !NET9_0_OR_GREATER
     /// <summary>
     ///     Splits a span of elements into sub-spans based on a delimiting element.