[Observability] [Exploratory View] adjust yaxis mode according to field format

[dominiqueclarke]

Summary

Fixes #117096
Fixes #116683

In exploratory view mutli series, we can have two y axis as the same time. Each y axis is formatted in a specific way according to the field format specified in the Data View. However, metrics in multi series were sometimes attributed to the wrong yaxis, resulting in incorrect formatting in the data displayed in the chart and in the popover.

Some background: the field format for the first column is what will be used by default for the right axis. When a metric is added that does not match the formatting for the first column, a second y axis is added.

So to resolve this issue, we check if the field format for the column matches the field format for the first column. If so, we can safely attribute this column to the right y axis. If not, we can assume it fits the left y axis.

Testing

Navigate to exploratory view
Select the KPI over time report type.
Add a series with synthetics data type and monitor duration metric
Add two more series, both with synthetics data type and down pings/up pings metric.
Ensure that the up/down pings are displayed as number without formatting, and the monitor duration is displayed as a duration with units
You can play around with next removing all series, then adding them back again in the opposite order, starting with down/up pings and ending with monitor duration. The popover format should still remain accurate.
You can continue to check different synthetics/rum metrics and their formatting. Ensure that the expected value is what is displayed in the tooltip

[elasticmachine]

Pinging @elastic/uptime (Team:uptime)

[dominiqueclarke]

@elasticmachine merge upstream

[shahzad31]

Code LGTM, @awahab07 or @lucasfcosta can one of you please do a functionality review on this. I am trying to do less work on kibana side this week.

[kibanamachine]

💚 Build Succeeded

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• Commit: fa02110
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Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
observability	377.0KB	377.3KB	+258.0B

History

• 💚 Build #4611 succeeded 91bb319

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@elasticmachine merge upstream

[shahzad31]

Functionality Looks good as well

[kibanamachine]

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[kibanamachine]

💚 Backport successful

Status	Branch	Result
✅	8.0
✅	7.16

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