Improve performance in LocateStartOfAssembly when running in .NET Core.

[brian-reichle]

BenchmarkDotNet v0.15.8, Windows 11 (10.0.26200.7840/25H2/2025Update/HudsonValley2)
Intel Core i7-9750H CPU 2.60GHz (Max: 2.59GHz), 1 CPU, 12 logical and 6 physical cores
.NET SDK 10.0.103
[Host] : .NET 10.0.3 (10.0.3, 10.0.326.7603), X64 RyuJIT x86-64-v3
.NET 10.0 : .NET 10.0.3 (10.0.3, 10.0.326.7603), X64 RyuJIT x86-64-v3
.NET 8.0 : .NET 8.0.24 (8.0.24, 8.0.2426.7010), X64 RyuJIT x86-64-v3

Method	Job	Text	Mean	Error	Ratio
NewLocateStartOfAssembly	.NET 10.0	Foo	4.486 ns	0.0729 ns	0.72
OldLocateStartOfAssembly	.NET 10.0	Foo	6.192 ns	0.0477 ns	1.00
NewLocateStartOfAssembly	.NET 8.0	Foo	6.612 ns	0.0444 ns	0.83
OldLocateStartOfAssembly	.NET 8.0	Foo	7.952 ns	0.1845 ns	1.00
NewLocateStartOfAssembly	.NET 10.0	Foo, (...)Quux" [24]	6.021 ns	0.0539 ns	0.75
OldLocateStartOfAssembly	.NET 10.0	Foo, (...)Quux" [24]	7.987 ns	0.0685 ns	1.00
NewLocateStartOfAssembly	.NET 8.0	Foo, (...)Quux" [24]	8.096 ns	0.0509 ns	0.75
OldLocateStartOfAssembly	.NET 8.0	Foo, (...)Quux" [24]	10.848 ns	0.0689 ns	1.00
NewLocateStartOfAssembly	.NET 10.0	Foo`2(...)bly]] [44]	62.429 ns	0.4451 ns	0.69
OldLocateStartOfAssembly	.NET 10.0	Foo`2(...)bly]] [44]	90.862 ns	0.6245 ns	1.00
NewLocateStartOfAssembly	.NET 8.0	Foo`2(...)bly]] [44]	67.481 ns	1.3844 ns	0.63
OldLocateStartOfAssembly	.NET 8.0	Foo`2(...)bly]] [44]	106.611 ns	0.9667 ns	1.00