Make spacing consistent between non-expandable and expandable list items

[sophypal]

This project uses semver, please check the scope of this pr:

• [ ] #none# - documentation fixes and/or test additions
• [x] #patch# - backwards-compatible bug fix
• [ ] #minor# - adding functionality in a backwards-compatible manner
• [ ] #major# - incompatible API change

no expansion - 10px left margin

expansion - 10px left margin and 7px between checkbox and chevron

CHANGELOG

• Updated margin/padding in the list-item to provide consistent spacing and follow UX specs

[coveralls]

Changes Unknown when pulling 05fd9dc308834dc1e9f6e79b5e4fd8c51c40e1a2 on sophypal:fix-styles into on ciena-frost:master.

[sophypal]

👍