changed test structure #174

Job	Run time
build-polypheny	8m 27s
build-docs	27s
test-stores (mongodb)	1m 51s
test-system-python (3.8, ubuntu-latest)	1m 19s
test-stores (hsqldb)	1m 15s
test-system-python (3.8, macos-latest)	1m 50s
test-stores (monetdb)	2m 16s
test-system-python (3.8, windows-latest)	2m 29s
test-stores (postgresql)	4m 13s
test-system-python (3.9, ubuntu-latest)	1m 36s
test-stores (file)	1m 21s
test-system-python (3.9, macos-latest)	1m 17s
test-stores (cottontail)	1m 35s
test-stores (neo4j)	2m 20s
test-system-python (3.9, windows-latest)	2m 28s
test-system-python (3.10, ubuntu-latest)	1m 29s
test-system-python (3.10, macos-latest)	1m 27s
test-system-python (3.10, windows-latest)	3m 39s
test-system-python (3.11, ubuntu-latest)	1m 34s
test-system-python (3.11, macos-latest)	1m 21s
test-system-python (3.11, windows-latest)	3m 18s
test-system-python (3.12, ubuntu-latest)	1m 28s
test-system-python (3.12, macos-latest)	1m 18s
test-system-python (3.12, windows-latest)	3m 7s
	53m 25s

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