Issues with loading from RXN file after saving to RXN several reactions positioned in a row

**Steps to Reproduce**
1. Add to Canvas two reactions in a row:
2. Click on Save as...
3. Click on Warnings and observe

**Actual Behavior**
A wrong warning is displayed: "The MDL Rxnfile V2000 format does not support drawn elements: reaction arrows will be lost:

**Expected behavior**
TBD - for example: Multistep reactions cannot be saved to this format. Only the first step will be saved

4. Check RXN preview and copy:
**Actual Behavior**
Reactants from two reactions are together on the left side, products from two reactions are together on the right side:

**Expected behavior**
Only the first reaction should be in RXN, so it should be 2:1

5. Paste to Canvas and observe

**Actual behavior**
Reactants from two reactions are together on the left side, products from two reactions are together on the right side:

**Expected behavior**
TBD - Only one first reaction 2:1 is pasted

**Environment details:**
- Ketcher [Version 2.24.0-rc.1] Build at 2024-08-06; 19:25:43
- Indigo Version 1.23.0-rc.1.0-g85f89b8f5-x86_64-linux-gnu-11.2.1
- OS: Windows 11 Enterprise
- Browser: Chrome, Version 127.0.6533.100 (Official Build) (64-bit)

**Additional context**
- Issue is related to https://github.com/epam/Indigo/issues/2194 and it was found during the investigation of Cascade Reactions feature https://github.com/epam/Indigo/issues/2128