fix(WindowLevelTool): fix calculation of image dynamic range

[pwespi]

Context

There is a type error in the calculation of the image dynamic range in the WindowLevelTool, which leads to a wrong multiplier.

Changes & Results

Fix calculation of image dynamic range in WindowLevelTool.

Testing

Checklist

PR

• [] My Pull Request title is descriptive, accurate and follows the
  semantic-release format and guidelines.

Code

• [] My code has been well-documented (function documentation, inline comments,
  etc.)

Public Documentation Updates

• [] The documentation page has been updated as necessary for any public API
  additions or removals.

Tested Environment

• [] "OS:
• [] "Node version:
• [] "Browser:

[sedghi]

is this just fixing our types?

[pwespi]

is this just fixing our types?

No, it's fixing the calculation. Sorry the description might have been confusing. calculatedDynamicRange is of type [number, number], but the Math.min calculation needs the difference of the two numbers. So line 198 is the actual fix.

[sedghi]

can you see why unit test failing?

[pwespi]

can you see why unit test failing?

There is a diff in some data:image/png;base64 data. I don't know how to interpret this.

[pwespi]

Updated the ground truth window level image.

[pwespi]

@sedghi tests are passing now.