Fix docker-validation CI job failure - load built image into Docker daemon

[Copilot]

The docker-validation CI job was failing because docker/build-push-action@v5 with the buildx driver only stores images in the build cache by default, not in the local Docker daemon where docker run expects to find them.

Changes

• Added load: true to the Docker build action in .github/workflows/pull-request.yml
  • This loads the built image into the local Docker daemon after building
  • Enables subsequent docker run commands to find the ccapi:test image

Context

The build action was producing this warning:

WARNING: No output specified with docker-container driver. Build result will only remain in the build cache.

The subsequent docker run step then failed with:

Unable to find image 'ccapi:test' locally
docker: Error response from daemon: pull access denied for ccapi, repository does not exist

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[Chesire]

The error I get is

Run docker run -d --name ccapi-test -p 8080:8080
docker run -d --name ccapi-test -p 8080:8080
-e SPRING_PROFILES_ACTIVE=dev
ccapi:test
shell: /usr/bin/bash -e {0}
Unable to find image 'ccapi:test' locally
docker: Error response from daemon: pull access denied for ccapi, repository does not exist or may require 'docker login': denied: requested access to the resource is denied
Run 'docker run --help' for more information
Error: Process completed with exit code 125.