Eliminate the duplicate functions used to group shipping time data

[eason9487]

Changes proposed in this Pull Request:

Closes #1426

This PR eliminates the duplicate functions used to group shipping time data.

• Move getCountriesTimeArray to the utils directory and rename to getShippingTimesGroups.
• Replace the getShippingTimesGroups function in the useSaveShippingTimes hook with the one in utils.
• Internalize the getShippingTimeMapKey util into getShippingTimesGroups util.
• Extra change: Remove an unreferenced AggregatedShippingTime type.

Detailed test instructions:

1. Go to step 2 of the onboarding flow.
2. Check if the shipping times can be saved correctly.
3. Go to the free listings editing page.
4. Check if the shipping times can be saved correctly.

Changelog entry

Dev - Eliminate the duplicate functions used to group shipping time data.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 63.5%. Comparing base (63ca753) to head (c9a7d61).

Files with missing lines	Patch %	Lines
...ngs/shipping-time-setup/shipping-countries-form.js	0.0%	1 Missing ⚠️
js/src/data/actions.js	0.0%	1 Missing ⚠️
js/src/utils/getShippingTimesGroups.js	50.0%	1 Missing ⚠️

Additional details and impacted files

@@                      Coverage Diff                      @@
##           fix/empty-max-shipping-time   #2726     +/-   ##
=============================================================
+ Coverage                         63.4%   63.5%   +0.1%     
=============================================================
  Files                              338     337      -1     
  Lines                             5203    5193     -10     
  Branches                          1274    1273      -1     
=============================================================
- Hits                              3301    3299      -2     
+ Misses                            1728    1721      -7     
+ Partials                           174     173      -1     

Flag	Coverage Δ
js-unit-tests	63.5% <50.0%> (+0.1%)	⬆️

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

Files with missing lines	Coverage Δ
js/src/data/reducer.js	82.5% <100.0%> (ø)
js/src/hooks/useSaveShippingTimes.js	31.6% <ø> (+5.7%)	⬆️
...ngs/shipping-time-setup/shipping-countries-form.js	0.0% <0.0%> (ø)
js/src/data/actions.js	15.8% <0.0%> (ø)
js/src/utils/getShippingTimesGroups.js	11.1% <50.0%> (ø)

[ianlin]

Thanks for cleaning up the duplicate functions. Confirmed saving shipping times works normally after those changes.