fix(multitenancy): update migrations assembly configuration in TenantDbContextFactory to read from configuration with default fallback (#1199)

Author: danieltharris

src/Modules/Multitenancy/Modules.Multitenancy/Data/TenantDbContextFactory.cs

@@ -19,15 +19,16 @@ public TenantDbContext CreateDbContext(string[] args)
         var provider = configuration["DatabaseOptions:Provider"] ?? "POSTGRESQL";
         var connectionString = configuration["DatabaseOptions:ConnectionString"]
             ?? "Host=localhost;Database=fsh-tenant;Username=postgres;Password=postgres";
-
+        var migrationsAssembly = configuration["DatabaseOptions:MigrationsAssembly"]
+            ?? "FSH.Playground.Migrations.PostgreSQL";
         var optionsBuilder = new DbContextOptionsBuilder<TenantDbContext>();
 
         switch (provider.ToUpperInvariant())
         {
             case "POSTGRESQL":
                 optionsBuilder.UseNpgsql(
                     connectionString,
-                    b => b.MigrationsAssembly("FSH.Playground.Migrations.PostgreSQL"));
+                    b => b.MigrationsAssembly(migrationsAssembly));
                 break;
             default:
                 throw new NotSupportedException($"Database provider '{provider}' is not supported for TenantDbContext migrations.");