Add hydrogens removes ABS label for molecule with Single Down bond

[AlexeyGirin]

Steps to Reproduce

1. Put on the canvas following SMILES: [#15]\[#15]\[#15]
2. Press Add/Remove implicit hydrogens button
   

Actual behavior
ABS label disappears

Expected behavior
ABS label remain in place

Ketcher version [e.g. v2.4.2].

• Indigo Toolkit Version 1.18.0.0-g73c32dec3-wasm32-wasm-clang-12.0.0
• Ketcher Version 2.19.0-rc.2 Build at 2024-03-11; 12:30:30
• Chrome Version Version 122.0.6261.112 (Official Build) (64-bit)
• Win10
• Issue found while testing Expose Fold/Unfold hydrogens function in indigo API #1436

[AlexeyGirin]

Find proper example

[AlexeyGirin]

Moved to Refined Backlog since not fixed over 2 releases