DevContainer: Alpine 3.22 (#7740)

Follow-up of https://github.com/FreshRSS/FreshRSS/pull/7627
https://gitlab.alpinelinux.org/alpine/aports/-/issues/17215 has been merged

.devcontainer/Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.21
+FROM alpine:3.22
 
 ENV TZ=UTC
 SHELL ["/bin/ash", "-eo", "pipefail", "-c"]