Add unfinished trait to investment factories

Now the code is symmetrical since we also use `finished`.

spec/factories/budgets.rb

@@ -114,6 +114,10 @@ FactoryBot.define do
       valuation_finished { true }
     end
 
+    trait :unfinished do
+      valuation_finished { false }
+    end
+
     trait :selected do
       selected { true }
       feasibility { "feasible" }

spec/features/admin/budget_investments_spec.rb

@@ -346,7 +346,7 @@ describe "Admin budget investments" do
       valuator = create(:valuator, user: user)
       create(:budget_investment,
         :with_administrator,
-        valuation_finished: false,
+        :unfinished,
         title: "Investment without valuation",
         budget: budget,
         valuators: [valuator])

spec/features/budgets/investments_spec.rb

@@ -1263,7 +1263,7 @@ describe "Budget Investments" do
 
     investment = create(:budget_investment,
                         :unfeasible,
-                        valuation_finished: false,
+                        :unfinished,
                         budget: budget,
                         group: group,
                         heading: heading,

spec/models/budget/investment_spec.rb

@@ -1228,10 +1228,7 @@ describe Budget::Investment do
       let(:params) { { advanced_filters: ["under_valuation"], budget_id: budget.id } }
       it "returns only investment under valuation" do
         valuator1 = create(:valuator)
-        investment1 = create(:budget_investment,
-          :with_administrator,
-          valuation_finished: false,
-          budget: budget)
+        investment1 = create(:budget_investment, :with_administrator, :unfinished, budget: budget)
         investment1.valuators << valuator1
         create(:budget_investment, :with_administrator, budget: budget)
         create(:budget_investment, budget: budget)