fix: tests when KEEP_PAST_RUNS is defined #11

Job	Run time
Build models (gfs)	1m 46s
Additional tests (node ${{ matrix.node }}, mongo ${{ matrix.mongo }})	0s
Run tests	1m 32s
Build models (arpege)	1m 50s
Build models (arome)	1m 2s
Build loaders (gfs, world)	1m 4s
Build loaders (gfs, isobaric-world)	55s
Build loaders (arpege, world)	52s
Build loaders (arpege, isobaric-world)	1m 2s
Build loaders (arpege, europe)	1m 6s
Build loaders (arpege, isobaric-europe)	54s
Build loaders (arome, france)	1m 6s
Build loaders (arome, france-high)	1m 1s
	14m 10s

Provide feedback