Merge pull request #1496 from ConnorJC3/update-speculative-execution

Update speculative execution of docker buildx to check buildkit daemon type

hack/provenance

@@ -20,12 +20,15 @@
 # in installations of buildx that do not correctly report their version
 # via `docker buildx version`.
 #
+# Additionally, if the local buildkit worker is the Docker daemon,
+# attestation should not be supported and must be disabled.
+#
 # Thus, this script echos back the flag `--provenance=false` if and only
 # if the local buildx installation supports it. If not, it exits silently.
 
 BUILDX_TEST=`docker buildx build --provenance=false 2>&1`
 if [[ "${BUILDX_TEST}" == *"See 'docker buildx build --help'."* ]]; then
-  if [[ "${BUILDX_TEST}" == *"requires exactly 1 argument"* ]]; then
+  if [[ "${BUILDX_TEST}" == *"requires exactly 1 argument"* ]] && ! docker buildx inspect | grep -qE "^Driver:\s*docker$"; then
     echo "--provenance=false"
   fi
 else