private long toInnerOffset(long offset) {
        // use relative offsets for compressed messages with magic v1
        if (magic > 0 && compression.type() != CompressionType.NONE)
            return offset - baseOffset;
        return offset;
    }
Append the record at the next consecutive offset. If no records have been appended yet, use the base
offset of this builder.
@param record The record to add
clients/src/main/java/org/apache/kafka/common/record/MemoryRecordsBuilder.java