CircleCI seems to run with /bin/sh, so use simple shell test.
@@ -107,7 +107,7 @@ gen-image-targets:
done ;\
/bin/echo "" >>$(MK_IMAGE_TARGETS) ;\
/bin/echo -e "\tmanifest-tool push from-args --platforms $(PLATFORMS) --template $(REGISTRY)/$${binary}:$(TAG)-ARCH --target $(REGISTRY)/$${binary}:$(TAG)" >>$(MK_IMAGE_TARGETS) ;\
- if [[ "$(TAG)" == "master" ]]; then \
+ if [ "$(TAG)" = "master" ]; then \
/bin/echo -e "\tmanifest-tool push from-args --platforms $(PLATFORMS) --template $(REGISTRY)/$${binary}:$(TAG)-ARCH --target $(REGISTRY)/$${binary}:latest" >>$(MK_IMAGE_TARGETS) ;\
fi ;\
/bin/echo "" >>$(MK_IMAGE_TARGETS) ;\
