Raise coverage + upgrade to node v18

[sverhoeven]

Due to https://github.com/i-VRESSE/workflow-builder/blob/16fef21dd76c90764da907db1c8496fd49e61ad9/packages/core/vitest.config.ts#L8 any file not exercised by tests will get 0% coverage.

This PR adds some more tests to raise the coverage.

Tried to use https://storybook.js.org/docs/react/writing-tests/test-runner, but failed capturing coverage. So instead wrote tests using https://testing-library.com/docs/react-testing-library/intro/ and https://react-hooks-testing-library.com/

The store test loads the zip library which required TransformStream to be defined. TransformStreams is not defined in node 16, but it is in node 18 so performed node upgrade.

Should be merged after #111

[netlify[bot]]

✅ Deploy Preview for wonderful-noether-53a9e8 ready!

Name	Link
🔨 Latest commit	071fc3a85c0c1f72d19f20c485f45d44ee572113
🔍 Latest deploy log	https://app.netlify.com/sites/wonderful-noether-53a9e8/deploys/62eccd0e4205890009ac8355
😎 Deploy Preview	https://deploy-preview-112--wonderful-noether-53a9e8.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.

[codecov-commenter]

Codecov Report

Merging #112 (c55f2ba) into main (16fef21) will increase coverage by 28.68%. The diff coverage is 100.00%.

@@             Coverage Diff             @@
##             main     #112       +/-   ##
===========================================
+ Coverage   32.61%   61.29%   +28.68%     
===========================================
  Files          55       55               
  Lines        3741     3741               
  Branches      219      275       +56     
===========================================
+ Hits         1220     2293     +1073     
+ Misses       2517     1444     -1073     
  Partials        4        4               

Flag	Coverage Δ
core-unit	56.78% <ø> (+24.08%)	:arrow_up:
form-unit	77.80% <100.00%> (+45.51%)	:arrow_up:

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

Impacted Files	Coverage Δ
packages/form/src/CollapsibleField.tsx	75.78% <100.00%> (+75.78%)	:arrow_up:
packages/core/src/toml.ts	98.12% <0.00%> (+1.49%)	:arrow_up:
packages/form/src/molecule/formats.ts	100.00% <0.00%> (+3.57%)	:arrow_up:
packages/core/src/archive.ts	27.77% <0.00%> (+27.77%)	:arrow_up:
packages/core/src/GripVertical.tsx	33.33% <0.00%> (+33.33%)	:arrow_up:
packages/core/src/utils/array.ts	36.84% <0.00%> (+36.84%)	:arrow_up:
packages/core/src/VisualNode.tsx	39.00% <0.00%> (+39.00%)	:arrow_up:
packages/core/src/workflow.ts	39.18% <0.00%> (+39.18%)	:arrow_up:
packages/core/src/catalog.ts	41.86% <0.00%> (+41.86%)	:arrow_up:
packages/core/src/DndWrapper.tsx	52.72% <0.00%> (+52.72%)	:arrow_up:
... and 8 more