Add conversion test from entity to file (ECC-7368)

[louiswesterheide]

Add test for the correct conversion of a file entity to a file.

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
init.py	0	0	100%
testing.py	43	11	74%	63-64 68 72 81-83 92 96 100 104
dataintegration/init.py	0	0	100%
dataintegration/context.py	53	0	100%
dataintegration/description.py	180	16	91%	46 134-135 139 149 154 168 174 210 224 226 233 348 389 397-398
dataintegration/discovery.py	49	36	27%	27 38-43 55-62 64 66-68 70 84-85 87-90 92-93 95-100 106 108
dataintegration/entity.py	27	1	96%	62
dataintegration/plugins.py	28	5	82%	20 24 28 32 47
dataintegration/ports.py	15	1	93%	32
dataintegration/types.py	112	11	90%	77 89 97 107 142 146-148 158 162 263
dataintegration/parameter/init.py	0	0	100%
dataintegration/parameter/choice.py	23	1	96%	26
dataintegration/parameter/code.py	52	0	100%
dataintegration/parameter/dataset.py	33	5	85%	30-32 51 54
dataintegration/parameter/graph.py	45	8	82%	42 66 69 72-74 84-85
dataintegration/parameter/multiline.py	4	4	0%	3 6 9-10
dataintegration/parameter/password.py	26	13	50%	11-13 17 34-37 39-40 47-49
dataintegration/parameter/resource.py	17	0	100%
dataintegration/typed_entities/init.py	6	0	100%
dataintegration/typed_entities/file.py	30	0	100%
dataintegration/typed_entities/typed_entities.py	21	2	90%	44-45
dataintegration/utils/init.py	38	13	66%	23 25 29 39-46 49-50
dataintegration/utils/entity_builder.py	86	0	100%
TOTAL	888	127	86%

Tests	Skipped	Failures	Errors	Time
33	1 💤	0 ❌	0 🔥	13.576 ⏱