Fix: Avoid duplicate key error with time scales at millisecond precision

[protyze]

When using the Line-Chart as a timeline with Date-Objects on the X-Axis, the AxisTicks and GridLines are using a string representation of the x-Values' Date-Object as the react element's "key". This causes duplicate keys when the timelines scale is below 1 second intervals (since a date-objects string representation does only include seconds, for example: "Thu Sep 16 2021 09:40:59 GMT+0100 (Western European Summer Time)").

This is a small PR to use the timestamp (.valueOf()) as the react element's key for AxisTicks and GridLines, so that the Line Chart works correctly with milliseconds precision.

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[netzwerg]

This is currently blocking some of our UI work – how can we support you in moving this PR forward?

[protyze]

Hi @plouc , anything we can do to get this merged?

[plouc]

@protyze, I'm afraid not, I'm just super busy with work atm.

[stale]

This pull request has been automatically marked as stale. If this pull request is still relevant, please leave any comment (for example, "bump"), and we'll keep it open. We are sorry that we haven't been able to prioritize reviewing it yet. Your contribution is very much appreciated.

[netzwerg]

bump

[plouc]

Good catch! And sorry for the late review.