fix: Dockerfile to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-ALPINE311-APKTOOLS-1534687
- https://snyk.io/vuln/SNYK-ALPINE311-BUSYBOX-1920756
- https://snyk.io/vuln/SNYK-ALPINE311-OPENSSL-1569451
- https://snyk.io/vuln/SNYK-ALPINE311-OPENSSL-1569451
- https://snyk.io/vuln/SNYK-ALPINE311-ZLIB-2977081

Dockerfile

@@ -1,4 +1,4 @@
-FROM node:15.14.0-alpine
+FROM node:21.0-alpine
 
 # Create app directory
 WORKDIR /app