core: stdcm: fix post-processing when arrival time is set #15192

Job	Run time
Check dockerfiles	9s
Build (core-build, core)	2m 14s
Check generated railjson sync	21s
Build (editoast, editoast-test)	14s
Check scripts	5s
Build (gateway-test, gateway-standalone, gateway-front)	1m 18s
Build (front-build, front-tests, front-devel, front-nginx)	15s
Check commits	10s
Build (osrdyne, osrdyne-test)	16s
Check railjson generator	1m 51s
Check final newline	7s
Check integration tests	1m 24s
Check infra schema sync	22s
Check osrd schema	39s
Check toml	5s
Check reuse compliance	9s
Check editoast lints	9m 3s
Check front rtk sync	1m 37s
Check core	4m 12s
Check editoast tests	6m 28s
Check osrdyne	3m 40s
Check front	2m 43s
Check editoast openapi	1m 2s
Check gateway	3m 28s
End to end tests	12m 33s
Integration tests	1m 4s
	55m 29s

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