Merge branch 'main' of https://github.com/dotnet/runtime into unroll-…

…startswith

# Conflicts:
#	src/libraries/System.Private.CoreLib/src/System/String.Comparison.cs

src/libraries/System.Private.CoreLib/src/System/String.Comparison.cs

@@ -1046,10 +1046,6 @@ static int GetNonRandomizedHashCodeOrdinalIgnoreCaseSlow(string str)
         //
         public bool StartsWith(string value!!)
         {
-            if (value is null)
-            {
-                throw new ArgumentNullException(nameof(value));
-            }
             return CultureInfo.CurrentCulture.CompareInfo.IsPrefix(this, value, GetCaseCompareOfComparisonCulture(StringComparison.CurrentCulture));
         }