make SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL configurable (#13301)

Author: valentijnscholten

dojo/settings/settings.dist.py

@@ -165,6 +165,7 @@
     DD_SOCIAL_AUTH_GITHUB_ENTERPRISE_API_URL=(str, ""),
     DD_SOCIAL_AUTH_GITHUB_ENTERPRISE_KEY=(str, ""),
     DD_SOCIAL_AUTH_GITHUB_ENTERPRISE_SECRET=(str, ""),
+    DD_SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL=(bool, True),
     DD_SAML2_ENABLED=(bool, False),
     # Allows to override default SAML authentication backend. Check https://djangosaml2.readthedocs.io/contents/setup.html#custom-user-attributes-processing
     DD_SAML2_AUTHENTICATION_BACKENDS=(str, "djangosaml2.backends.Saml2Backend"),
@@ -559,7 +560,7 @@ def generate_url(scheme, double_slashes, user, password, host, port, path, param
 SOCIAL_AUTH_STRATEGY = "social_django.strategy.DjangoStrategy"
 SOCIAL_AUTH_STORAGE = "social_django.models.DjangoStorage"
 SOCIAL_AUTH_ADMIN_USER_SEARCH_FIELDS = ["username", "first_name", "last_name", "email"]
-SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL = True
+SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL = env("DD_SOCIAL_AUTH_USERNAME_IS_FULL_EMAIL")
 
 GOOGLE_OAUTH_ENABLED = env("DD_SOCIAL_AUTH_GOOGLE_OAUTH2_ENABLED")
 SOCIAL_AUTH_GOOGLE_OAUTH2_KEY = env("DD_SOCIAL_AUTH_GOOGLE_OAUTH2_KEY")