Update requirements.txt

requirements.txt

@@ -19,6 +19,7 @@ Flask-Babel==2.0.0
 flask-roles==0.5
 Flask-SeaSurf==0.3.0
 flask-restx==0.2.0
+flask-whooshalchemy3==0.2.0
 SQLAlchemy==1.3.23
 psycopg2==2.8.6
 wget==3.2