Use 2 spaces in sha1sum

Works in alpine too
diff --git a/Dockerfile b/Dockerfile
index 3221c9a..b4594fa 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -29,7 +29,7 @@
 
 # Use tini as subreaper in Docker container to adopt zombie processes 
 RUN curl -fsSL https://github.com/krallin/tini/releases/download/v0.5.0/tini-static -o /bin/tini && chmod +x /bin/tini \
-  && echo "$TINI_SHA /bin/tini" | sha1sum -c -
+  && echo "$TINI_SHA  /bin/tini" | sha1sum -c -
 
 COPY init.groovy /usr/share/jenkins/ref/init.groovy.d/tcp-slave-agent-port.groovy
 
@@ -42,7 +42,7 @@
 # could use ADD but this one does not check Last-Modified header 
 # see https://github.com/docker/docker/issues/8331
 RUN curl -fsSL http://repo.jenkins-ci.org/public/org/jenkins-ci/main/jenkins-war/${JENKINS_VERSION}/jenkins-war-${JENKINS_VERSION}.war -o /usr/share/jenkins/jenkins.war \
-  && echo "$JENKINS_SHA /usr/share/jenkins/jenkins.war" | sha1sum -c -
+  && echo "$JENKINS_SHA  /usr/share/jenkins/jenkins.war" | sha1sum -c -
 
 ENV JENKINS_UC https://updates.jenkins-ci.org
 RUN chown -R ${user} "$JENKINS_HOME" /usr/share/jenkins/ref