[enrich] Fix 'roles' attribute error

The 'roles' attribute wasn't available for all the
enrichers. The attribute has been added to the
main class 'Enrich' so subclasses will have it
available even when they don't use it.

Signed-off-by: Santiago Dueñas <sduenas@bitergia.com>

grimoire_elk/enriched/enrich.py

@@ -101,6 +101,7 @@ class Enrich(ElasticItems):
     analyzer = Analyzer
     sh_db = None
     kibiter_version = None
+    roles = []
     RAW_FIELDS_COPY = ["metadata__updated_on", "metadata__timestamp",
                        "offset", "origin", "tag", "uuid"]
     KEYWORD_MAX_LENGTH = 1000  # this control allows to avoid max_bytes_length_exceeded_exception

releases/unreleased/roles-attribute-not-available-on-some-enrichers.yml

@@ -0,0 +1,10 @@
+---
+title: Roles attribute not available on some enrichers
+category: fixed
+author: Santiago Dueñas <sduenas@bitergia.com>
+issue: null
+notes: >
+  The 'roles' attribute wasn't available for all the
+  enrichers. The attribute has been added to the
+  main class 'Enrich' so subclasses will have it
+  available even when they don't use it.