我尝试在我的系统中实现下面提到的代码。我收到如下错误:LOGGER ERROR: Invalid charset: UTF-8
LOGGER ERROR: Illegal severity level: error
`writer3 = json
writer3.level = error
writer3.file = logs/log-{count}.json
writer3.field.level = level
writer3.field.source = {class}.{method}()
writer3.field.message = message
writer3.charset = UTF-8
writer3.append = true
writer3.buffered = true`