ref(eventstream): Remove unnecessary try/except (#51843)

We can remove this now since generic-events has a schema

Needs https://github.com/getsentry/sentry/pull/51842

src/sentry/eventstream/snuba.py

@@ -422,18 +422,13 @@ class SnubaEventStream(SnubaProtocolEventStream):
 
         serialized_data = json.dumps(data)
 
-        try:
-            codec = sentry_kafka_schemas.get_codec(
-                topic={
-                    "events": "events",
-                    "transactions": "transactions",
-                    "search_issues": "generic-events",
-                }[entity]
-            )
-        except (sentry_kafka_schemas.SchemaNotFound, KeyError):
-            # Needed since "generic-events" does not have a schema yet
-            codec = sentry_kafka_schemas.codecs.json.JsonCodec(None)
-
+        codec = sentry_kafka_schemas.get_codec(
+            topic={
+                "events": "events",
+                "transactions": "transactions",
+                "search_issues": "generic-events",
+            }[entity]
+        )
         codec.decode(serialized_data.encode("utf-8"), validate=True)
 
         try: