Change tenants.id column type from string to uuid

Updated the tenants migration to use $table->uuid('id')->primary()
instead of $table->string('id')->primary() to properly support UUID-based
tenant identification and ensure consistency with Stancl Tenancy expectations.

assets/migrations/2019_09_15_000010_create_tenants_table.php

@@ -16,7 +16,7 @@ return new class extends Migration
     public function up(): void
     {
         Schema::create('tenants', function (Blueprint $table) {
-            $table->string('id')->primary();
+            $table->uuid('id')->primary();
 
             // your custom columns may go here