chore: Replace su-exec with setpriv for Kapacitor alpine

Author: srebhan

kapacitor/1.8/alpine/Dockerfile

@@ -1,7 +1,7 @@
 FROM alpine:3.20
 
 RUN echo 'hosts: files dns' >> /etc/nsswitch.conf
-RUN apk add --no-cache ca-certificates su-exec && \
+RUN apk add --no-cache ca-certificates && \
     update-ca-certificates
 
 ENV KAPACITOR_VERSION 1.8.0

kapacitor/1.8/alpine/entrypoint.sh

@@ -11,5 +11,5 @@ export KAPACITOR_HOSTNAME
 if [ "$(id -u)" -ne 0 ] || [ "${KAPACITOR_AS_ROOT}" = "true" ]; then
     exec "$@"
 else
-    exec su-exec kapacitor "$@"
+    exec setpriv --reuid kapacitor --regid kapacitor --init-groups "$@"
 fi