restructure tests

.../supertoken/restrictions/restrictionIsTighterThan_test.go

internal/supertoken/restrictions/restriction_test.go

...al/supertoken/restrictions/restrictionsGetExpires_test.go

.../supertoken/restrictions/restrictionsGetNotBefore_test.go

internal/utils/issuerUtils/issuerUtilsCombineSubIss_test.go

...nal/utils/issuerUtils/issuerUtilsCompareIssuerURL_test.go

internal/utils/issuerUtils/issuerUtils_test.go

internal/utils/utilsCombineURLPath_test.go

internal/utils/utilsIntersectSlices_test.go

internal/utils/utilsIsSubSet_test.go

internal/utils/utilsSliceUnion_test.go

internal/utils/utilsStringInSlice_test.go

internal/utils/utilsUniqueSlice_test.go

internal/utils/utils_test.go