tests: fix flaky test with hardcoded ID #13796

Job	Run time
check_generated_railjson_sync	25s
build (core-build, core)	24s
build (editoast, editoast-test)	25s
build (gateway-test, gateway-standalone, gateway-front)	1m 12s
check_commits	10s
build (front-build, front-tests, front-devel, front-nginx)	17s
build (osrdyne, osrdyne-test)	23s
check_integration_tests	1m 21s
check_railjson_generator	1m 52s
Check final newline	8s
check_osrd_schema	38s
check_infra_schema_sync	24s
check_reuse_compliance	8s
check_toml	8s
check_editoast_tests	6m 53s
check_core	4m 44s
check_editoast_openapi	1m 5s
check_editoast_lints	8m 53s
check_front_rtk_sync	1m 35s
check_gateway	3m 16s
check_osrdyne	3m 42s
check_front	2m 26s
integration_tests	10m 28s
	50m 57s

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