The job was canceled because "ubuntu-latest_6_0_x" failed.

The operation was canceled.

Possible null reference argument for parameter 'buffer' in 'Task MemoryStream.WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)'.

Possible null reference return.

Change the 'WriteAsync' method call to use the 'Stream.WriteAsync(ReadOnlyMemory<byte>, CancellationToken)' overload (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1835)

Use 'string.Contains(char)' instead of 'string.Contains(string)' when searching for a single character (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1847)

Use 'string.Contains(char)' instead of 'string.Contains(string)' when searching for a single character (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1847)

Indexing can be simplified (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/ide0056)

Using directive is unnecessary. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/style-rules/ide0005)