Fix not properly configuring jackson to use default value for unknown enum values

Author: Laupetin

src/main/java/org/synyx/matrix/bot/MatrixClient.java

@@ -40,6 +40,7 @@ public MatrixClient(String hostname, String username, String password) {
         .addModule(new JavaTimeModule())
         .configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
         .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
+        .configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE, true)
         .build();
     this.api = new MatrixApi(hostname, authentication, objectMapper);
     this.state = null;