US or EU Data Region Selection (#3752)

* add selection of data region for push

* fix cargo check + rewrite config + add check url

* fix clippy error

* add comment in .env.template, adapt config.rs

* Update .env.template

Co-authored-by: William Desportes <williamdes@wdes.fr>

* Update .env.template

Co-authored-by: William Desportes <williamdes@wdes.fr>

* Revert "Update .env.template"

This reverts commit 5bed974ba7b9f481792d2228834585f053d47dc3.

* Revert "Update .env.template"

This reverts commit 0760eff95dfaf2a9cf97bb25f6cf7660bdf55173.

* fix /connect/token to push identity

* fix /connect/token to push identity

* Fixed formatting when solving merge conflicts

---------

Co-authored-by: William Desportes <williamdes@wdes.fr>
Co-authored-by: Daniel García <dani-garcia@users.noreply.github.com>

.env.template

@@ -77,11 +77,13 @@
 # WEBSOCKET_PORT=3012
 
 ## Enables push notifications (requires key and id from https://bitwarden.com/host)
+## If you choose "European Union" Data Region, uncomment PUSH_RELAY_URI and PUSH_IDENTITY_URI then replace .com by .eu
 # PUSH_ENABLED=true
 # PUSH_INSTALLATION_ID=CHANGEME
 # PUSH_INSTALLATION_KEY=CHANGEME
 ## Don't change this unless you know what you're doing.
 # PUSH_RELAY_URI=https://push.bitwarden.com
+# PUSH_IDENTITY_URI=https://identity.bitwarden.com
 
 ## Controls whether users are allowed to create Bitwarden Sends.
 ## This setting applies globally to all users.
@@ -462,4 +464,4 @@
 ## HaveIBeenPwned API Key, request it here: https://haveibeenpwned.com/API/Key
 # HIBP_API_KEY=
 
-# vim: syntax=ini
+# vim: syntax=ini