Resolve "Move solar cell tests to plugin"

Closes #2054 (closed)

tests/data/datamodel/metainfo/eln/perovskite_database/eqe_file.dat

-4.13333333333333	0.040481675
-4	0.108612
-3.875	0.2376965
-3.75757575757576	0.36020825
-3.64705882352941	0.4609545
-3.54285714285714	0.5603
-3.44444444444445	0.5699975
-3.35135135135135	0.56795025
-3.26315789473684	0.531854
-3.17948717948718	0.57506175
-3.1	0.60372325
-3.02439024390244	0.67570025
-2.95238095238095	0.75112525
-2.88372093023256	0.80349175
-2.81818181818182	0.830106
-2.75555555555556	0.84012675
-2.69565217391304	0.817607
-2.63829787234043	0.832261
-2.58333333333333	0.833554
-2.53061224489796	0.828813
-2.48	0.832261
-2.43137254901961	0.83818725
-2.38461538461539	0.84465225
-2.33962264150943	0.85241025
-2.2962962962963	0.85930625
-2.25454545454545	0.86555575
-2.21428571428571	0.86706425
-2.17543859649123	0.8609225
-2.13793103448276	0.84723825
-2.10169491525424	0.83042925
-2.06666666666667	0.8143745
-2.0327868852459	0.800367
-2	0.7975655
-1.96825396825397	0.801229
-1.9375	0.80586225
-1.90769230769231	0.80844825
-1.87878787878788	0.817607
-1.85074626865672	0.82094725
-1.82352941176471	0.82159375
-1.79710144927536	0.8156675
-1.77142857142857	0.8178225
-1.74647887323944	0.81028
-1.72222222222222	0.80844825
-1.6986301369863	0.80262975
-1.67567567567568	0.7967035
-1.65333333333333	0.7583445
-1.63157894736842	0.61449825
-1.61038961038961	0.40083
-1.58974358974359	0.14837175
-1.56962025316456	0.05018995
-1.55	0.015785375
-1.53086419753086	0.0034081325
-1.51219512195122	6.9940525E-4
\ No newline at end of file