Multiplayer synchronized doesn't emit synchronized signal with REPLICATION_MODE_ON_CHANGE properties

### Tested versions

Tested on vanilla 4.2.1 and 4.2.2 (Custom build, but it doesn't mess with core functionality nor multiplayer stuff)

### System information

Godot v4.2.2.rc (fb28924c5) - Arch Linux #1 ZEN SMP PREEMPT_DYNAMIC Wed, 29 Nov 2023 00:40:39 +0000 - X11 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2060 (nvidia; 545.29.06) - Intel(R) Core(TM) i9-10900KF CPU @ 3.70GHz (20 Threads)

### Issue description

So, apparently, `MultiplayerSynchronizer` won't emit `synchronized` signal when properties with `REPLICATION_MODE_ON_CHANGE` replication mode get synced.

### Steps to reproduce

1. Setup a basic network environment
2. Create a multiplayer syncrhonizer node
3. Add a property with "On change" sync mode
4. Connect the `synchronized` signal to a desired node
5. Enjoy the sadness

### Minimal reproduction project (MRP)

[MP2.zip](https://github.com/godotengine/godot/files/14341181/MP2.zip)

Start with the attached MP2.zip minimal reproduction and the MultiplayerSynchronizer behavior described in the issue. Verify whether properties using REPLICATION_MODE_ON_CHANGE trigger the synchronized signal, then confirm the signal is emitted for that case without breaking other synchronization modes.

Written by the indexing model from the issue text.