minor change [ci skip]

Signed-off-by: munishchouhan <[email protected]>

Author: munishchouhan

src/main/groovy/io/seqera/wave/service/builder/DockerBuildStrategy.groovy

@@ -127,6 +127,7 @@ class DockerBuildStrategy extends BuildStrategy {
     protected List<String> cmdForSingularity(BuildRequest req) {
         final wrapper = ['docker',
                          'run',
+                         '--rm',
                          '--privileged',
                          '-e',
                          "AWS_ACCESS_KEY_ID=${System.getenv('AWS_ACCESS_KEY_ID')}".toString(),