[PM-24549] Remove feature flag: use-pricing-service (#6567)

* Remove feature flag and move StaticStore plans to MockPlans for tests

* Remove old plan models / move sponsored plans out of StaticStore

* Run dotnet format

* Add pricing URI to Development appsettings for local development and integration tests

* Updated Api Integration tests to get current plan type

* Run dotnet format

* Fix failing tests

test/Core.Test/Billing/Mocks/Plans/FreePlan.cs

@@ -0,0 +1,48 @@
+using Bit.Core.Billing.Enums;
+using Bit.Core.Models.StaticStore;
+
+namespace Bit.Core.Test.Billing.Mocks.Plans;
+
+public record FreePlan : Plan
+{
+    public FreePlan()
+    {
+        Type = PlanType.Free;
+        ProductTier = ProductTierType.Free;
+        Name = "Free";
+        NameLocalizationKey = "planNameFree";
+        DescriptionLocalizationKey = "planDescFree";
+
+        UpgradeSortOrder = -1; // Always the lowest plan, cannot be upgraded to
+        DisplaySortOrder = -1;
+
+        PasswordManager = new FreePasswordManagerFeatures();
+        SecretsManager = new FreeSecretsManagerFeatures();
+    }
+
+    private record FreeSecretsManagerFeatures : SecretsManagerPlanFeatures
+    {
+        public FreeSecretsManagerFeatures()
+        {
+            BaseSeats = 2;
+            BaseServiceAccount = 3;
+            MaxProjects = 3;
+            MaxSeats = 2;
+            MaxServiceAccounts = 3;
+
+            AllowSeatAutoscale = false;
+        }
+    }
+
+    private record FreePasswordManagerFeatures : PasswordManagerPlanFeatures
+    {
+        public FreePasswordManagerFeatures()
+        {
+            BaseSeats = 2;
+            MaxCollections = 2;
+            MaxSeats = 2;
+
+            AllowSeatAutoscale = false;
+        }
+    }
+}