build(deps): bump node from 20-alpine to 21-alpine in /build (nodejs#…

…2803)

Bumps node from 20-alpine to 21-alpine.

---
updated-dependencies:
- dependency-name: node
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

build/Dockerfile

@@ -1,4 +1,4 @@
-FROM node:20-alpine@sha256:4559bc033338938e54d0a3c2f0d7c3ad7d1d13c28c4c405b85c6b3a26f4ce5f7
+FROM node:21-alpine@sha256:d3271e4bd89eec4d97087060fd4db0c238d9d22fcfad090a73fa9b5128699888
 
 ARG UID=1000
 ARG GID=1000