incWithExemplar({
		labels = this.defaultLabels,
		value = this.defaultValue,
		exemplarLabels = this.defaultExemplarLabelSet,
	} = {}) {
		const res = this.incWithoutExemplar(labels, value);
		this.updateExemplar(exemplarLabels, value, res.labelHash);
	}
Increment counter with exemplar, same as inc but accepts labels for an
exemplar.
If no label is provided the current exemplar labels are kept unchanged
(defaults to empty set).

@param {object} incOpts - Object with options about what metric to increase
@param {object} incOpts.labels - What label you want to be incremented,
                                 defaults to null (metric with no labels)
@param {Number} incOpts.value - Value to increment, defaults to 1
@param {object} incOpts.exemplarLabels - Key-value  labels for the
                                         exemplar, defaults to empty set {}
@returns {void}