fix(slider): ensure margin-block is correct for range variant

[Westbrook]

Description

Correct margin-block-start in Range variant of Slider component.

fixes #1205

How and where has this been tested?

• How this was tested: Visually inspecting the local build of the documentation site
• Browser(s) and OS(s) this was tested with: Stable Chrome on Catalina

Screenshots

Before:

After:

To-do list

• If my change impacts other components, I have tested to make sure they don't break.
• If my change impacts documentation, I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.

• This pull request is ready to merge.

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[castastrophe]

I suspect PR #1547 will end up superseding this so I've highlighted this PR there to ensure changes address this concern.

[bernhard-adobe]

I suspect PR #1547 will end up superseding this so I've highlighted this PR there to ensure changes address this concern.

yes @castastrophe. This is part of #1547 where the padding has been corrected for Range and regular Slider variant.

[castastrophe]

Awesome, thanks @bernhard-adobe for confirming and thank you @Westbrook for the contribution! Closing this out in favor of the rewrite work.