chore: preparation for spec rendering order

[markov00]

Summary

This PR is the first one to that allow us to implement a valid and clear method to sort the splitted series and allow custom rendering order of bars/area/lines in either chart, legend and tooltips.

This PR in particular clean up few small items:

• include the parsing action that that is useful to distinguish in which state we are when updating a spec. This will also ensure that the default setting component is always part of the specs array
• split the tooltipValues array into an header and an array with only the metric values.

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• Any consumer-facing exports were added to src/index.ts (and stories only import from ../src except for test data & storybook)
• This was checked for cross-browser compatibility, including a check against IE11
• Proper documentation or storybook story was added for features that require explanation or tutorials
• Unit tests were updated or added to match the most common scenarios
• Each commit follows the convention

[codecov-io]

Codecov Report

Merging #516 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #516   +/-   ##
=======================================
  Coverage   71.49%   71.49%           
=======================================
  Files         208      208           
  Lines        6118     6118           
  Branches     1137     1169   +32     
=======================================
  Hits         4374     4374           
  Misses       1727     1727           
  Partials       17       17

---

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 8dede8c...c434a08. Read the comment docs.

[rshen91]

These changes LGTM - thanks for updating all the tests and including chart_state.specs.test.ts. I ran this storybook locally and all the stories appeared to be rendering correctly!