ci: update backend dockerfile

Author: cardoso

apps/meteor/.docker/Dockerfile.backend

@@ -1,4 +1,4 @@
-FROM node:22.16.0-alpine3.20 AS builder
+FROM node:22.16.0-alpine3.22 AS builder
 
 ENV LANG=C.UTF-8
 
@@ -13,7 +13,7 @@ RUN cd /app/bundle/programs/server \
     && npm uninstall sharp \
     && npm install --omit=dev sharp@0.33.5
 
-FROM node:22.16.0-alpine3.20
+FROM node:22.16.0-alpine3.22
 
 LABEL maintainer="buildmaster@rocket.chat"