Pin async-timeout to 4.0.3 and update pip dependencies

Change-Id: Ib39800c316b44591b3b801f413e44d9eacd29ce7
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/requirements.txt b/requirements.txt
index d22fe95..cdb9420 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,8 +14,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #######################################################################################
-async-timeout==5.0.1
-    # via retrying-async
+async-timeout==4.0.3
+    # via
+    #   -r requirements.in
+    #   retrying-async
 bcrypt==4.2.1
     # via paramiko
 cachetools==5.5.0