fix: Dynamically compute default zoom/center for map traces

[camdecoster]

Description

Use lat/lon points to dynamically compute the default zoom/center for scattermap and densitymap traces.

Closes #7674.

Changes

• Add check during handleDefaults to dynamically computer map bounds
• Add tests
• Linting/formatting

Screenshots

Before	After

Testing

• Be on master
• Run the following mock through Plotly devtools

  {
    "data": [
      {
        "hovertext": ["San Marino", "Cairo", "Istanbul", "Trondheim"],
        "lat": [43.9360958, 30.06263, 41.01384, 63.43049],
        "lon": [12.4417702, 31.24967, 28.94966, 10.39506],
        "marker": { "color": "#f00" },
        "mode": "markers",
        "type": "scattermap"
      }
    ],
    "layout": { "width": 900, "height": 600 }
  }

• Note that the Trondheim point is outside of the frame
• Switch to this branch
• Run the same mock
• Note that the scatter points are nicely framed
• Pan/zoom around
• Click the reset view button
• Note that the view is still nicely framed

Notes

• This PR is a combination of work done by me, @palmerusaf (Dynamic map defaults #7692), and @DhruvGarg111 ([BUG]: Default zoom and center for scattermap traces does not show all points #7674)
• This is landing in v4.0, so it will be on by default. Users that don't want auto-framing should specify a center and/or zoom.
• The first commit handles linting/formatting for a couple of files. That commit can be ignored during review.