fix: update values for default timezone selector

[eschutho]

SUMMARY

There was a bug where if GMT was selected, the value was being passed in as the readable GMT, etc which is not a valid timezone. This PR fixes that issue.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

You should be able to select GMT from the timezone dropdown in the alerts/reports modal and it should save properly and run the report with no errors.

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[codecov]

Codecov Report

Merging #17124 (2f1b49b) into master (c2e1ab6) will increase coverage by 0.02%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##           master   #17124      +/-   ##
==========================================
+ Coverage   76.88%   76.91%   +0.02%     
==========================================
  Files        1031     1034       +3     
  Lines       55183    55398     +215     
  Branches     7505     7554      +49     
==========================================
+ Hits        42430    42608     +178     
- Misses      12501    12540      +39     
+ Partials      252      250       -2     

Flag	Coverage Δ
javascript	70.91% <87.50%> (+0.09%)	⬆️

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

Impacted Files	Coverage Δ
...frontend/src/components/TimezoneSelector/index.tsx	97.77% <87.50%> (+0.05%)	⬆️
...mponents/nativeFilters/FiltersConfigModal/utils.ts	65.64% <0.00%> (-4.73%)	⬇️
...onfigModal/FiltersConfigForm/FiltersConfigForm.tsx	69.25% <0.00%> (-2.36%)	⬇️
...erset-frontend/src/datasource/DatasourceEditor.jsx	71.91% <0.00%> (-1.94%)	⬇️
...eFilters/FiltersConfigModal/FiltersConfigModal.tsx	87.50% <0.00%> (-1.85%)	⬇️
superset-frontend/src/reduxUtils.ts	69.76% <0.00%> (-1.67%)	⬇️
...-frontend/src/datasource/ChangeDatasourceModal.tsx	86.36% <0.00%> (-1.14%)	⬇️
...frontend/src/dashboard/components/Header/index.jsx	68.71% <0.00%> (-0.78%)	⬇️
...rontend/src/dashboard/containers/DashboardPage.tsx	0.00% <0.00%> (ø)
...src/components/FilterableTable/FilterableTable.tsx	81.86% <0.00%> (ø)
... and 21 more

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[betodealmeida]

A question about using Africa/Abidjan.

[betodealmeida]

Can we use GMT here instead? It's an official IANA time zone identifier.

If not, it might be good to say here that the Africa/Abidjan timezone has no daylight saving, so it will be identical to GMT all year long.

[eschutho]

Gotcha, the reason that this value is used is because when we dedupe the time zone list, we choose the first value, which happens to be this one. The user never sees the value, just the label, and it has the same exact time zone match as GMT (no daylight savings time). Do you think this might pose a problem somewhere? Many of the other time zones do the same thing. PT for example is actually Vancouver.

[betodealmeida]

Ah, I see. I think it's fine. Maybe leave a comment saying that timezones are deduped by the first alphabetical value?

[geido]

Super nit. I think we agreed that the convention should be Timezone selector

Suggested change

	ariaLabel={t('Timezone Selector')}
	ariaLabel={t('Timezone selector')}

[eschutho]

thank you for pointing that out. 👍

[eschutho]

@yousoph