chore(deps): update drakkan/sftpgo docker tag to v2.6.4 (#2618)

* chore(deps): update drakkan/sftpgo docker tag to v2.6.4

* Update app version [skip ci]

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Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: github-action update-app-version <githubaction@githubaction.com>

sftpgo/2.6.4-alpine/docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   sftpgo:
-    image: drakkan/sftpgo:v2.6.3-alpine
+    image: drakkan/sftpgo:v2.6.4-alpine
     container_name: ${CONTAINER_NAME}
     networks:
       - 1panel-network