fix: samples/server/petstore/ruby-sinatra/Dockerfile to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-ALPINE316-BUSYBOX-6913410
- https://snyk.io/vuln/SNYK-ALPINE316-BUSYBOX-6913410
- https://snyk.io/vuln/SNYK-ALPINE316-MUSL-8720632
- https://snyk.io/vuln/SNYK-ALPINE316-MUSL-8720632

Author: snyk-bot

samples/server/petstore/ruby-sinatra/Dockerfile

@@ -1,5 +1,5 @@
 ## Build libraries
-FROM ruby:3.0-alpine as rubydev
+FROM ruby:3.4.4-alpine as rubydev
 
 ## for thin or falcon
 #RUN apk --no-cache add make g++ libc-dev
@@ -13,7 +13,7 @@ RUN bundle config set path lib
 RUN bundle install
 
 ## Build Runtime image
-FROM ruby:3.0-alpine
+FROM ruby:3.4.4-alpine
 
 RUN apk --no-cache add tzdata ## ca-certificates