chore(deps): update zabbix/zabbix-agent:alpine-7.0-latest docker digest to 5286501 (#2203)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| zabbix/zabbix-agent | digest | `71f1f22` → `5286501` |

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devenv/zabbix70/docker-compose.yml

@@ -73,7 +73,7 @@ services:
       POSTGRES_PASSWORD: zabbix
 
   zabbix-agent:
-    image: zabbix/zabbix-agent:alpine-7.0-latest@sha256:71f1f22b3828f47b714a1bbef39b456453e0e552461d138f36e18a35732302ba
+    image: zabbix/zabbix-agent:alpine-7.0-latest@sha256:52865010468af7f6dc3e3dbd45b645c32b8d133f4a230301cea26ffa679d5cc4
     environment:
       ZBX_SERVER_HOST: zabbix-server
       ZBX_SERVER_PORT: 10051