add `atob` option to `fromError` typing

[OutdatedVersion]

Description

Adds missing property to fromError options so its easily discoverable.

How Has This Been Tested?

Verified type matches source usage and in a consuming project using module augmentation

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

I think

Checklist:

• [ ] node_modules/.bin/jscs -c .jscsrc stacktrace.js passes without errors
• [x] npm test passes without errors
• [x] I have read the contribution guidelines
• [ ] I have updated the documentation accordingly
• [ ] I have added tests to cover my changes