Update CSRF decorators to use @csrf_exempt instead of @csrf.exempt

- Change import to from flask_wtf.csrf import csrf_exempt
- Replace @csrf.exempt with @csrf_exempt decorators

app/upload/routes.py

@@ -5,7 +5,7 @@ import shutil
 from flask import request, jsonify, render_template, redirect, url_for, flash, current_app
 from flask_login import login_required, current_user
 from flask_jwt_extended import jwt_required, get_jwt_identity
-from flask_wtf import csrf
+from flask_wtf.csrf import csrf_exempt
 from werkzeug.utils import secure_filename
 from app.upload import bp
 from app import db
@@ -905,7 +905,7 @@ def upload_fixture_zip(fixture_id):
         return redirect(request.referrer or url_for('main.fixtures'))
 
 @bp.route('/chunk', methods=['POST'])
-@csrf.exempt
+@csrf_exempt
 @login_required
 @require_active_user
 def upload_chunk():
@@ -946,7 +946,7 @@ def upload_chunk():
         return jsonify({'success': False, 'error': str(e)}), 500
 
 @bp.route('/finalize', methods=['POST'])
-@csrf.exempt
+@csrf_exempt
 @login_required
 @require_active_user
 def finalize_upload():