function gocbcore.EncodeCommonFlags totally ignores the compression type when it generates a flag object
example:
flags := gocbcore.EncodeCommonFlags(gocbcore.JSONType, gocbcore.UnknownCompression)
_, compression := gocbcore.DecodeCommonFlags(flags)
fmt.Println("compressio is unknown?", compression == gocbcore.UnknownCompression) // returns false
https://go.dev/play/p/Tj7yqRWHHI6