Don't fail the build when MUI key is missing

[felipecruz91]

Context: #94 (comment)

Given the REACT_APP_MUI_LICENSE_KEY is not shared in the repo, we should not make the docker build operation fail if it's not present:

Before

$ make build-extension

docker buildx build \
		--secret id=BUGSNAG_API_KEY \
		--secret id=REACT_APP_MUI_LICENSE_KEY \
		--build-arg BUGSNAG_RELEASE_STAGE=local \
		--build-arg BUGSNAG_APP_VERSION=latest \
		--load \
		--tag=docker/volumes-backup-extension:latest \
		.
ERROR: failed to stat REACT_APP_MUI_LICENSE_KEY: stat REACT_APP_MUI_LICENSE_KEY: no such file or directory
make: *** [build-extension] Error 1

[atomist]

Dockerfile

docker/volumes-backup-extension:pr-95

Vulnerabilities

Comparison

👏 No new critical or high vulnerabilities compared with target branch main

---

More details are available in the vulnerability report

[github-actions]

Docker image tag(s) pushed:

docker/volumes-backup-extension:pr-95

Labels added to images:

org.opencontainers.image.title=volumes-backup-extension
org.opencontainers.image.description=Back up, clone, restore, and share Docker volumes effortlessly.
org.opencontainers.image.url=https://github.com/docker/volumes-backup-extension
org.opencontainers.image.source=https://github.com/docker/volumes-backup-extension
org.opencontainers.image.version=pr-95
org.opencontainers.image.created=2022-10-21T12:26:15.826Z
org.opencontainers.image.revision=680c8f1cb88c9afa241c08f84fc6994777f59978
org.opencontainers.image.licenses=Apache-2.0