Support language script subtags #1418

Job	Run time
Check toolchain is stable	3s
QA (build-all-features)	6m 22s
QA (check-all-features)	4m 4s
Check URLs	8s
QA (lint)	2m 17s
Check for unused dependencies	14s
Build book	12s
Unit tests (macos-latest, stable)	58s
Unit tests (windows-latest, stable)	1m 43s
SSR end to end tests (initial_language_from_url_param_axum, initial_language_from_cookie_actix, i...	2m 19s
Unit tests (ubuntu-latest, nightly)	35s
Unit tests (ubuntu-latest, stable)	37s
Unit tests (macos-latest, nightly)	1m 16s
CSR end to end tests (chrome, macos-latest)	2m 4s
Build example (csr-minimal, stable, ubuntu-latest)	48s
Build example (ssr-hydrate-actix, stable, ubuntu-latest)	3m 35s
CSR end to end tests (chrome, ubuntu-latest)	1m 2s
CSR end to end tests (firefox, windows-latest)	3m 25s
Build example (csr-complete, stable, windows-latest)	1m 33s
Build example (ssr-hydrate-actix, nightly, ubuntu-latest)	1m 58s
Build example (csr-complete, stable, ubuntu-latest)	23s
Build example (ssr-hydrate-axum, nightly, ubuntu-latest)	57s
Build example (csr-complete, stable, macos-latest)	43s
CSR end to end tests (firefox, ubuntu-latest)	1m 44s
CSR end to end tests (chrome, windows-latest)	2m 30s
Deploy book	0s
Report type sizes	24s
Test leptos-fluent-macros release	21s
Test leptos-fluent release	9s
Release leptos-fluent-macros	0s
Release leptos-fluent	0s
Create release	0s
	42m 24s

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