Update base Docker image to Node 16

[pkosiec]

No description provided.

[codecov]

Codecov Report

Merging #185 (6d221c2) into main (33cac01) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #185   +/-   ##
=======================================
  Coverage   93.50%   93.50%           
=======================================
  Files          18       18           
  Lines         277      277           
  Branches       51       51           
=======================================
  Hits          259      259           
  Misses          7        7           
  Partials       11       11           

Flag	Coverage Δ
cli	93.75% <ø> (ø)
core	93.42% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

---

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 33cac01...6d221c2. Read the comment docs.