⬆️ Update ghcr.io/home-assistant/aarch64-base Docker tag to v3.21

Author: renovate[bot]

logspout/build.yaml

@@ -1,6 +1,6 @@
 # https://developers.home-assistant.io/docs/add-ons/configuration#add-on-dockerfile
 build_from:
-  aarch64: "ghcr.io/home-assistant/aarch64-base:3.20"
+  aarch64: "ghcr.io/home-assistant/aarch64-base:3.21"
   amd64: "ghcr.io/home-assistant/amd64-base:3.20"
   armhf: "ghcr.io/home-assistant/armhf-base:3.20"
   armv7: "ghcr.io/home-assistant/armv7-base:3.20"