Add sonar scanner

Dockerfile

@@ -19,4 +19,12 @@ LABEL org.opencontainers.image.created="${IMAGE_CREATED}" \
       org.opencontainers.image.description="Docker images used by act_runner to run workflows."
 
 RUN apt-get update && \
-	apt-get -y install gnupg2
+	apt-get -y install gnupg2 openjdk-21-jre-headless
+
+RUN wget -O sonar.zip https://binaries.sonarsource.com/Distribution/sonar-scanner-cli/sonar-scanner-cli-6.1.0.4477.zip && \
+	unzip sonar.zip && \
+	mkdir /sonar && \
+	mv sonar-scanner-*/* /sonar && \
+	rm -r sonar-scanner-* sonar.zip
+
+ENV PATH="$PATH:/sonar/bin"