revert: "feat!: upgrade Node.js to 14 LTS (#1393)"

[VerteDinde]

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• The changes are appropriately documented (if applicable).
• The changes have sufficient test coverage (if applicable).
• The testsuite passes successfully on my local machine (if applicable).

Summarize your changes:
This reverts commit c6b4c78, allowing us to release a new version of packager before a breaking change.

[malept]

once tests pass

[codecov]

Codecov Report

Merging #1398 (7b17d18) into main (7dcaf44) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1398   +/-   ##
=======================================
  Coverage   95.61%   95.61%           
=======================================
  Files          15       15           
  Lines         776      776           
=======================================
  Hits          742      742           
  Misses         34       34           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more