fix: Typo in fips build workflow (kyma-project#4616)

Author: dbadura

.github/workflows/busola-build.yml

@@ -58,4 +58,4 @@ jobs:
       dockerfile: Dockerfile.fips
       tags: ${{ inputs.tag != '' && inputs.tag || 'latest' }}
       use-restricted-registry: true
-      build-args: BASE_IMAGE=europe-docker.pkg.dev/kyma-project/prod/busola@${needs.build-busola-image.outputs.digest}
+      build-args: BASE_IMAGE=europe-docker.pkg.dev/kyma-project/prod/busola@${{ needs.build-busola-image.outputs.digest }}