Migration to remove WebAuthn 2FA method from Free users (#3271)

* Created migration for review.

* Added in check for org users that have Premium through their org.

* Commented out UPDATE for testing.

* Changes from PR Review

* Added U2F handling.

* Address PR feedback

* Updated to use string for type comparision due to bad data in Prod database.

* Added revision date to update and uncommented update for migration run.

(cherry picked from commit 2149266)

util/Migrator/DbScripts/2023-09-14_00_Remove_WebAuthn_For_Free_Users.sql

@@ -0,0 +1,68 @@
+-- Assumptions:
+-- When a 2FA method is disabled, it is removed from the TwoFactorProviders array
+
+-- Problem statement:
+-- We have users who currently do not have any available 2FA method, with the only one being
+-- WebAuthn, which is effectively disabled by a server-side permission check for Premium status.
+-- With WebAuthn being made free, we want to avoid these users suddenly being forced
+-- to provide 2FA using a key that they haven't used in a long time, by deleting that key from their TwoFactorProviders.
+
+DECLARE @UsersWithoutPremium TABLE
+(
+    Id UNIQUEIDENTIFIER,
+    TwoFactorProviders NVARCHAR(MAX)
+);
+
+DECLARE @TwoFactorMethodsForUsersWithoutPremium TABLE
+(
+    Id UNIQUEIDENTIFIER,
+    TwoFactorType NVARCHAR(50)
+)
+
+DECLARE @UsersToAdjust TABLE
+(
+    Id UNIQUEIDENTIFIER
+);
+
+-- Insert users who don't have Premium
+INSERT INTO @UsersWithoutPremium
+SELECT u.Id, u.TwoFactorProviders
+from [User] u
+WHERE u.Premium = 0;
+
+-- Filter out those users who get Premium from their org
+DELETE FROM @UsersWithoutPremium
+WHERE Id IN 
+    (SELECT UserId 
+    FROM [OrganizationUser] ou 
+    INNER JOIN [Organization] o on o.Id = ou.OrganizationId WHERE o.Enabled = 1 AND o.UsersGetPremium = 1)
+
+-- From users without Premium, get their enabled 2FA methods
+INSERT INTO @TwoFactorMethodsForUsersWithoutPremium
+SELECT  u.Id, 
+        tfp1.[key] as TwoFactorType
+FROM @UsersWithoutPremium u
+CROSS APPLY OPENJSON(u.TwoFactorProviders) tfp1
+CROSS APPLY OPENJSON(tfp1.[value]) WITH (
+   [Enabled] BIT '$.Enabled'
+) tfp2
+WHERE [Enabled] = 1 -- We only want enabled 2FA methods
+
+INSERT INTO @UsersToAdjust
+SELECT t1.Id
+FROM @TwoFactorMethodsForUsersWithoutPremium t1
+WHERE t1.TwoFactorType = '7'
+AND NOT EXISTS 
+    (SELECT * 
+    FROM @TwoFactorMethodsForUsersWithoutPremium t2 
+    WHERE t2.Id = t1.Id AND t2.TwoFactorType <> '7' AND t2.TwoFactorType <> '4')
+
+SELECT *
+FROM @UsersToAdjust
+
+DECLARE @revisionDate DATETIME2(7) = GETUTCDATE();
+
+UPDATE [User]
+SET TwoFactorProviders = NULL, RevisionDate = @revisionDate
+FROM @UsersToAdjust ua
+WHERE ua.Id = [User].Id