[0.15.10] Blueprint Library changes signals

[Optera]

It seems the blueprint library sometimes uses wrong signal indices for blueprints when taking blueprints from saves with different versions/mod configurations.

To replicate:
- open the attached save without any mods
- use the RR crossing blueprint from the Railway book in the library and compare it with the existing crossing.

Result:
red signal was replaced by H and green with I.

The RR crossing blueprint right inside the library works however.