PDCL-5086: optional chaining is only available in node >= 14, which i…

[brenthosie]

…s higher than our recommendation

Description

During development of #43 , the optional chaining syntax was introduced to solve the problem. Optional chaining is only available in node >= 14, however, we recommend that users can use node 12.

Related Issue

https://jira.corp.adobe.com/browse/PDCL-5086

Motivation and Context

Bug fix to allow users on older node versions to use uploader

How Has This Been Tested?

1. npm test
2. manual verification that uploading can happen using node 12

Screenshots (if appropriate):

Types of changes

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

Checklist:

• [x] I have signed the Adobe Open Source CLA.
• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.