Add support for decoding JSON Text Sequences (RFC 7464) and CBOR Sequences (RFC 8742)

Basically decode an input sequence as QCborArray or QJsonArray without having the outer markers indicating that it is an array. For JSON, this will need to properly interpret the delimiters (CBOR requires no delimiter).

For CBOR, we may want to add an extra SequenceStop parameter with two values:

• SequenceStop::AtBreak
• SequenceStop::AtEOF (default)

Proposed API:

• QCborValue::fromCborSequence()
• QJsonDocument::fromJsonSequence() (maybe add directly to QJsonValue and stop adding to QJsonDocument?)