Currently when using `unit` parameter in the `rate` aggregator in time series mode (meaning the `rate` aggregation is defined as a child aggregation of `time_series` aggregation) then this parameter is ignored. We should investigate whether this parameter can be supported for computing rate in time series mode.
x-pack/plugin/analytics/src/main/java/org/elasticsearch/xpack/analytics/rate/InternalResetTrackingRate.java
public static final String NAME = "rate_with_resets";
    private final double startValue;
    private final double endValue;
    private final long startTime;
    private final long endTime;
    private final double resetCompensation;
    protected InternalResetTrackingRate(
        String name,
        DocValueFormat format,
        Map<String, Object> metadata,
        double startValue,
        double endValue,
        long startTime,
        long endTime,
        double resetCompensation
    ) {
        super(name, format, metadata);
        this.startValue = startValue;
        this.endValue = endValue;
        this.startTime = startTime;
        this.endTime = endTime;
        this.resetCompensation = resetCompensation;
    }
    public InternalResetTrackingRate(StreamInput in) throws IOException {
        super(in, false);
        this.startValue = in.readDouble();
        this.endValue = in.readDouble();
        this.startTime = in.readLong();
        this.endTime = in.readLong();
        this.resetCompensation = in.readDouble();