Add Image Scan to PR Build (#250)

*Description of changes:*
- Adding `artifacts_build` step to `pr-build` workflow for JS images to
get vulnerability scanning during PR builds.
See the same for
[Java](https://github.com/aws-observability/aws-otel-java-instrumentation/blob/main/.github/workflows/pr-build.yml#L145)
and
[Python](https://github.com/aws-observability/aws-otel-python-instrumentation/blob/main/.github/workflows/pr-build.yml#L23)

- Delete duplicate `docker logout` step in artifact_build. Doesn't
effect PR builds from forked repos:

https://github.com/aws-observability/aws-otel-js-instrumentation/actions/runs/16950181911/job/48040937542?pr=251

*Testing*
Successful run:
https://github.com/aws-observability/aws-otel-js-instrumentation/actions/runs/16949767942

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choice.

Author: liustve

.github/workflows/pr-build.yml

@@ -38,6 +38,15 @@ jobs:
         run: npm ci
       - name: Compile all NPM projects
         run: npm run compile
+      - name: Build Tarball and Image Files
+        uses: ./.github/actions/artifacts_build
+        with:
+          image_uri_with_tag: pr-build/${{ matrix.node }}
+          push_image: false
+          load_image: true
+          node_version: ${{ matrix.node }}
+          package_name: aws-distro-opentelemetry-node-autoinstrumentation
+          os: ubuntu-latest
       - name: Build Lambda Layer
         run: npm run build-lambda
       - name: Unit tests (Full)