chore: bump cbl-mariner/base/nodejs from 16 to 18 in /examples/msal-node

Bumps cbl-mariner/base/nodejs from 16 to 18.

---
updated-dependencies:
- dependency-name: cbl-mariner/base/nodejs
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

examples/msal-node/Dockerfile

@@ -1,6 +1,6 @@
 ARG BASEIMAGE=mcr.microsoft.com/mirror/gcr/distroless/nodejs-debian11:16
 
-FROM mcr.microsoft.com/cbl-mariner/base/nodejs:16 as build-env
+FROM mcr.microsoft.com/cbl-mariner/base/nodejs:18 as build-env
 ADD . /app
 WORKDIR /app
 RUN npm install