viriato import: trains with no intermediate steps should not have a red dot

[maelysLeratRosso]

What happened?

when importing a Viriato file, the number of intermediate steps is displayed

Here the 3rd train has no intermediate step (so only origin and destination) and its dot is in red -> it should be blue

What did you expect to happen?

The case where the dot should be red is if there is less at two path steps, so if the number of intermediate steps is <0 (and not <=0 currently)

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

as above

On which environments the bug occurs?

Dev (SNCF)

On which browser the bug occurs?

Google Chrome

OSRD version (top right corner Account button > Informations)

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