A VERY small modification in code sample needed

In one of sample of this page in section Process Text Data and method `TryParseLine`, in case of finding a byte with `'\r' `content which is not the last byte of segment too, we check for the next byte to be` '\n'` and `break` in this case. But in case that the next byte not be` '\n' `we continue loop which is okay. The point is that we should reset index variable to `-1` here to identify the code that no line yet found in code. Of course I am not sure that how adding `'\r' `without a `'\n' `after it could be happen but it is may be the case in test texts.
The edited code could be as followed:

```
while (buffer.TryGet(ref position, out ReadOnlyMemory segment))
{

var span = segment.Span;
index = span.IndexOf((byte)'\r');
if (index > -1)
{
// Does the index is last byte of segment?
if (index == span.Length - 1)
{
// We should search next byte in next segment for \n
var next = position;
if (buffer.TryGet(ref next, out ReadOnlyMemory nextSegment))
{
if (nextSegment.Span[0] == (byte)'\n')
{
// line found
break;
}
}
else
{
return false;
}
}
else
{
// The index is not the last byte of span so compare next byte in this segment

if (span[index + 1] == (byte)'\n')
{
// line found inside one segment
break;
}
else
{
index = -1;
}
}
}
copy = position;// this should be for all non-break cases
}
```

---
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* ID: b9a7a159-0d11-531b-a444-cb154cd09967
* Version Independent ID: 73a2ecb2-17d6-4f36-4b59-5e3cf619edf1
* Content: [System.Buffers - .NET](https://learn.microsoft.com/en-us/dotnet/standard/io/buffers)
* Content Source: [docs/standard/io/buffers.md](https://github.com/dotnet/docs/blob/main/docs/standard/io/buffers.md)
* Product: **dotnet-fundamentals**
* GitHub Login: @Rick-Anderson
* Microsoft Alias: **riande**