[Heatmap] Time scale type with a single row of data breaks the chart

[darnautov]

Describe the bug
Passing a single row of data with a time scale on the X-axis breaks the chart.

To Reproduce
Go to https://codesandbox.io/s/cool-sound-8j9m7?file=/src/App.tsx

Notice by not setting the xDomain with a single values, causes the error below.

Expected behaviour
The chart is rendered with a single row of data

Version (please complete the following information):

• OS: [e.g. iOS] macOS
• Browser: [e.g. chrome, safari] Chrome
• Elastic Charts: [e.g. 1.0.1] latest

Errors in browser console

quantize.js:18 Uncaught RangeError: Invalid array length
    at rescale (quantize.js:18)
    at Function.scale.range (quantize.js:28)
    at Object.shapeViewModel (viewmodel.js:81)
    at Object.render (scenegraph.js:30)
    at geometries.js:42
    at resultFuncWithRecomputations (index.js:77)
    at index.js:70
    at index.js:30
    at index.js:84
    at index.js:30

[markov00]

I've lowered the priority because this issue has a workaround (set the minInterval in the xDomain)

[markov00]

Starting from v39.0.0 the Heatmap has a new set of APIs that fix and cover this issue #1462 by explicitly requiring the internal parameter when using a time scale