Flaky unit test suite

RepeatingTestFixture.cs

var elaboration = new Stage() { Type = StageType.Elaboration, Name = "Elaboration" };
var approval = new Stage() { Type = StageType.Approval, Name = "Approval" };
var consensus = new Stage() { Type = StageType.Approval, Name = "Consensus" };

context.Stages.Add(elaboration);
context.Stages.Add(approval);
context.Stages.Add(consensus);

var oldCategory = new Category()
{
    Initials = "CAT",
    Name = "Category",
    Stages = new List<CategoryStage>() {
        new CategoryStage() { Order = 1, Stage = elaboration },
        new CategoryStage() { Order = 2, Stage = approval },
    },
};
var newCategory = new Category()
{
    Initials = "DOG",
    Name = "Dogcary",
    Stages = new List<CategoryStage>() {
        new CategoryStage() { Order = 1, Stage = elaboration },
        new CategoryStage() { Order = 2, Stage = consensus },
    }
};

context.Categories.Add(oldCategory);
context.Categories.Add(newCategory);

var document = new Document()
{
    CategoryId = oldCategory.Id,
    SuggestedCode = new SuggestedCode() { Code = 5, DocumentId = 1 },
    ProcessId = 1,
    Title = "Arroz",
    Code = "Codecept",
    Stages = new List<DocumentStage>() {
        new DocumentStage() {
            StageId = elaboration.Id,
            Responsibles = new List<DocumentStageResponsible>()
            {
                new DocumentStageResponsible() { ResponsibleId = 113 },
            },
        },
        new DocumentStage()
        {
            StageId = approval.Id,
            Responsibles = new List<DocumentStageResponsible>()
            {
                new DocumentStageResponsible() { ResponsibleId = 113 },
                new DocumentStageResponsible() { ResponsibleId = 117 },
            },
        },
    },
    Revisions = new List<Revision>()
    {
        new Revision() {
            Stages = new List<RevisionStage>(),
            PublishDate = DateTime.Now,
            RevisionRequestHistory = new List<RevisionRequest>()
        },
    }
};