Fix the histogram rendering in Grafana 10

[kyle-sammons]

Summary

Currently under Grafana 10.x, the histogram rendering for this plugin is broken. This is due to a subtle and slight shift to the data returned by one of the APIs. This PR fixes it so that it works under both 9.x and 10.x

Demo

Using Grafana 10.3

Using Grafana 9.5

Requirements (place an x in each [ ])

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
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The following point can be removed after setting up CI (such as Travis) with coverage reports (such as Codecov)

• I've written tests to cover the new code and functionality included in this PR.

The following point can be removed after setting up a CLA reporting tool such as cla-assistant.io

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