fix(translations): add sl to acceptedLanguages (#9506)

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Fixes #

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### What?
This PR adds `'sl'` to list of accepted languages, dedupes languages not
implemented from langs that have been supported, and adjusts the string
match for `'sl'` in importDateFNSLocale to the correct locale.

### Why?
To fix TS errors and runtime errors encountered while adding Slovenian
language to config, and then selecting it in `/account` view.

### How?
- Addition of `'sl'` to `acceptLanguages` array
- Change from `'sl'` to `'sl-SI'` in `importDateFNSLocale.ts`

Fixes #9504

---------

Co-authored-by: Jessica Chowdhury <jessica@trbl.design>

Author: akhrarovsaid

packages/translations/src/importDateFNSLocale.ts

@@ -96,7 +96,7 @@ export const importDateFNSLocale = async (locale: string): Promise<Locale> => {
       result = (await import('date-fns/locale/sk')).sk
 
       break
-    case 'sl':
+    case 'sl-SI':
       result = (await import('date-fns/locale/sl')).sl
 
       break

packages/translations/src/languages/sl.ts

@@ -1,6 +1,6 @@
-import type { Language } from '../types.js'
+import type { DefaultTranslationsObject, Language } from '../types.js'
 
-export const slTranslations = {
+export const slTranslations: DefaultTranslationsObject = {
   authentication: {
     account: 'Račun',
     accountOfCurrentUser: 'Račun trenutnega uporabnika',

packages/translations/src/utilities/languages.ts

@@ -29,6 +29,7 @@ export const acceptedLanguages = [
   'rs-latin',
   'ru',
   'sk',
+  'sl',
   'sv',
   'th',
   'tr',
@@ -70,7 +71,6 @@ export const acceptedLanguages = [
    * 'gu',
    * 'ha-Latn',
    * 'hi',
-   * 'hr',
    * 'hy',
    * 'id',
    * 'ig-Latn',
@@ -108,7 +108,6 @@ export const acceptedLanguages = [
    * 'rw',
    * 'sd-Arab',
    * 'si',
-   * 'sl',
    * 'sq',
    * 'sr-Cyrl-BA',
    * 'sr-Cyrl-RS',