[C#] Fix assertion. #1025

Job	Run time
C# 8.0.x	2m 30s
C++ GCC 11 (Ubuntu 22.04)	1m 27s
C++ GCC 6 (Ubuntu 20.04)	1m 15s
C++ GCC 12 (Ubuntu 22.04)	1m 25s
Java 8 (ubuntu-22.04)	1m 6s
C++ GCC 7 (Ubuntu 20.04)	1m 36s
C++ GCC 13 (Ubuntu 22.04)	1m 41s
Java 8 (windows-latest)	1m 52s
C++ GCC 8 (Ubuntu 20.04)	1m 23s
Java 17 (ubuntu-22.04)	1m 42s
C++ GCC 9 (Ubuntu 20.04)	1m 24s
Java 17 (windows-latest)	2m 42s
C++ GCC 10 (Ubuntu 20.04)	1m 19s
Java 21 (ubuntu-22.04)	1m 37s
C++ Clang 13 (Ubuntu 22.04)	1m 13s
Java 21 (windows-latest)	2m 38s
C++ Clang 9 (Ubuntu 20.04)	1m 21s
C++ Clang 14 (Ubuntu 22.04)	1m 25s
C++ Clang 10 (Ubuntu 20.04)	1m 26s
C++ Clang 15 (Ubuntu 22.04)	1m 19s
C++ Xcode (macOS)	1m 34s
C++ MSVC (Windows) (windows-latest)	3m 51s
C++ Clang 16 (Ubuntu 22.04)	1m 23s
C++ Clang 11 (Ubuntu 20.04)	1m 22s
C++ Clang 17 (Ubuntu 22.04)	1m 39s
C++ Clang 12 (Ubuntu 20.04)	1m 36s
Golang 1.22.x	1m 1s
Rust stable	45s
Rust beta	52s
Rust nightly	56s
	47m 20s

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