changefeedccl: Envelope schema name reflects schema config

Fixes a bug where the Avro -envelope schema name, as opposed to subject,
 did not honor the schema prefix and full table name options.

Release note (bug fix): Envelope schema in avro registry now honors schema_prefix and full_table_name

pkg/ccl/changefeedccl/encoder.go

@@ -413,7 +413,7 @@ func (e *confluentAvroEncoder) EncodeValue(ctx context.Context, row encodeRow) (
 		}
 
 		opts := avroEnvelopeOpts{afterField: true, beforeField: e.beforeField, updatedField: e.updatedField}
-		registered.schema, err = envelopeToAvroSchema(row.tableDesc.GetName(), opts, beforeDataSchema, afterDataSchema)
+		registered.schema, err = envelopeToAvroSchema(e.rawTableName(row.tableDesc), opts, beforeDataSchema, afterDataSchema)
 		if err != nil {
 			return nil, err
 		}

pkg/ccl/changefeedccl/encoder_test.go

@@ -482,6 +482,10 @@ func TestAvroSchemaNaming(t *testing.T) {
 			`supermovr.public.drivers-key`,
 			`supermovr.public.drivers-value`,
 		})
+
+		//Both changes to the subject are also reflected in the schema name in the posted schemas
+		require.Contains(t, reg.mu.schemas[reg.mu.subjects[`supermovr.public.drivers-key`]], `supermovr`)
+		require.Contains(t, reg.mu.schemas[reg.mu.subjects[`supermovr.public.drivers-value`]], `supermovr`)
 	}
 
 	t.Run(`enterprise`, enterpriseTest(testFn))