Add Haystack index name in env vars

Signed-off-by: Emmy D'Anello <emmy.danello@animath.fr>

tfjm/settings_prod.py

@@ -44,7 +44,7 @@ HAYSTACK_CONNECTIONS = {
     'default': {
         'ENGINE': 'haystack.backends.elasticsearch7_backend.Elasticsearch7SearchEngine',
         'URL': 'http://elasticsearch:9200/',
-        'INDEX_NAME': 'haystack',
+        'INDEX_NAME': os.getenv('HAYSTACK_INDEX_NAME', 'inscription-tfjm'),
     }
 }