Update base image for Airflow to 2.5.2

Change-Id: Id73a0de10b80a4154e1816c5695d3c96de1b03fe
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/docker/Airflow/Dockerfile b/docker/Airflow/Dockerfile
index 5aa56a3..804cc7f 100644
--- a/docker/Airflow/Dockerfile
+++ b/docker/Airflow/Dockerfile
@@ -15,7 +15,7 @@
 # limitations under the License.
 #######################################################################################
 
-FROM apache/airflow:2.3.0-python3.8
+FROM apache/airflow:2.5.2-python3.8
 USER root
 RUN DEBIAN_FRONTEND=noninteractive apt-get --yes update && \
     DEBIAN_FRONTEND=noninteractive apt-get --yes install \