public void setTransactionIsolationLevel(TransactionIsolationLevel level) {
        if (level != TransactionIsolationLevel.UNKNOWN) {
            setTransactionIsolationLevel(level.intValue());
        }
    }
Set the transaction isolation level on the underlying connection if it is different from the current isolation level.

@param level the {@link TransactionIsolationLevel} to use.
@throws UnableToManipulateTransactionIsolationLevelException if isolation level is not supported by the underlying connection or JDBC driver.
core/src/main/java/org/jdbi/v3/core/Handle.java