chore(deps): update dependency redis to v3.5.3 (GoogleCloudPlatform#3926)

Author: renovate-bot

appengine/flexible/redis/requirements.txt

@@ -1,3 +1,3 @@
 Flask==1.1.2
 gunicorn==20.0.4
-redis==3.5.2
+redis==3.5.3

appengine/standard_python3/redis/requirements.txt

@@ -1,2 +1,2 @@
 Flask==1.1.2
-redis==3.5.2
+redis==3.5.3

appengine/standard_python37/redis/requirements.txt

@@ -1,2 +1,2 @@
 Flask==1.1.2
-redis==3.5.2
+redis==3.5.3

functions/memorystore/redis/requirements.txt

@@ -1 +1 @@
-redis==3.5.2
+redis==3.5.3

memorystore/redis/requirements.txt

@@ -13,5 +13,5 @@
 # [START memorystore_requirements]
 Flask==1.1.2
 gunicorn==20.0.4
-redis==3.5.2
+redis==3.5.3
 # [END memorystore_requirements]