Fix issue with get calls caused by latest swagger client

[sandeep-paliwal]

Fixes #52
With new swagger client 3.10.2 get calls were failing for empty body. Fixed this.

Description

Related Issue

Motivation and Context

How Has This Been Tested?

unit tests and e2e test.

Screenshots (if appropriate):

Types of changes

• 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:

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

[codecov]

Codecov Report

Merging #53 (7d5ed88) into master (6aeaf8c) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master       #53   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            3         3           
  Lines          491       491           
  Branches        76        76           
=========================================
  Hits           491       491           

Impacted Files	Coverage Δ
src/index.js	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6aeaf8c...7d5ed88. Read the comment docs.