fix: fix deprecated warnings

lib/exmr_web.ex

@@ -43,7 +43,7 @@ defmodule ExmrWeb do
         layouts: [html: ExmrWeb.Layouts]
 
       import Plug.Conn
-      use Gettext, backend: MyApp.Gettext
+      use Gettext, backend: ExmrWeb.Gettext
 
       unquote(verified_routes())
     end
@@ -85,7 +85,7 @@ defmodule ExmrWeb do
       import Phoenix.HTML
       # Core UI components and translation
       import ExmrWeb.CoreComponents
-      use Gettext, backend: MyApp.Gettext
+      use Gettext, backend: ExmrWeb.Gettext
 
       # Shortcut for generating JS commands
       alias Phoenix.LiveView.JS

lib/exmr_web/components/core_components.ex

@@ -17,7 +17,7 @@ defmodule ExmrWeb.CoreComponents do
   use Phoenix.Component
 
   alias Phoenix.LiveView.JS
-  use Gettext, backend: MyApp.Gettext
+  use Gettext, backend: ExmrWeb.Gettext
 
   @doc """
   Renders a modal.

lib/exmr_web/gettext.ex

@@ -5,7 +5,7 @@ defmodule ExmrWeb.Gettext do
   By using [Gettext](https://hexdocs.pm/gettext),
   your module gains a set of macros for translations, for example:
 
-      use Gettext, backend: MyApp.Gettext
+      use Gettext, backend: ExmrWeb.Gettext
 
       # Simple translation
       gettext("Here is the string to translate")