editoast: signals are not cached for search during import

[leovalais]

What happened?

During an infra import, track sections are imported after signals so when the insertion triggers of osrd_infra_signalmodel is triggered, the track section of the new signal doesn't exist yet and therefore the signal is not cached in osrd_search_signal.

What did you expect to happen?

The new signals should all be cached after the import completes.

How can we reproduce it (as minimally and precisely as possible)?

1. Import a new infra
2. Check osrd_search_signals
3. The signals of the new import are not there

What operating system, browser and environment are you using?

N/A

OSRD version (top right corner Account button > Informations)

dev

[celine-sncf]

@leovalais