Case Sensitivity of `in` and `!in` keywords do not match documentation

[tomas-pajurek]

According to Kusto documentation, keywords in and !in are case-sensitive by default and there are case-insensitive variants with ~. However, this parser library assigns SyntaxKind values the other way around, as can be seen here:

Kusto-Query-Language/src/Kusto.Language/Syntax/SyntaxFacts.cs

Line 157 in a121c72

new SyntaxData(SyntaxKind.InCsKeyword, "in~", opKind: OperatorKind.InCs),

[mattwar]

The server still executes correctly, and the client does not actually interpret these, so just the SyntaxFacts table is associated with a SyntaxKind enum that is misleading. I will investigate if changing this will be breaking to anyone, but I suspect it will. We might just have to leave it as it is.