fix: chmod +x in Dockerfile

Author: xhofe

example/Dockerfile

@@ -3,5 +3,5 @@ ARG TARGETPLATFORM
 LABEL MAINTAINER="[email protected]"
 WORKDIR /bin/
 COPY bin/${TARGETPLATFORM}/docker-actions ./
-RUN chmod+x /bin/docker-actions && \
+RUN chmod +x /bin/docker-actions && \
     /bin/docker-actions