🗃️(database) add missing migrations for user's language

Addressed missing migrations for the user's language field,
ensuring recent updates are correctly applied.

src/backend/core/migrations/0004_alter_user_language.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.0.7 on 2024-08-07 14:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0003_alter_room_configuration'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='user',
+            name='language',
+            field=models.CharField(choices="(('en-us', 'English'), ('fr-fr', 'French'))", default='en-us', help_text='The language in which the user wants to see the interface.', max_length=10, verbose_name='language'),
+        ),
+    ]