invert the docker env var checks

Author: lerouxb

.evergreen/start-atlas-cloud-cluster.sh

@@ -89,7 +89,7 @@ cleanup() {
 
 trap cleanup EXIT
 
-if [ -z "$DOCKERHUB_PASSWORD" ]; then
+if [ -n "$DOCKERHUB_PASSWORD" ]; then
   echo "Logging in to docker"
   echo "${DOCKERHUB_PASSWORD}" | docker login -u ${DOCKERHUB_USERNAME} --password-stdin
 fi

.evergreen/start-atlas-local.sh

@@ -19,7 +19,7 @@ cleanup() {
 
 trap cleanup EXIT
 
-if [ -z "$DOCKERHUB_PASSWORD" ]; then
+if [ -n "$DOCKERHUB_PASSWORD" ]; then
   echo "Logging in to docker"
   echo "${DOCKERHUB_PASSWORD}" | docker login -u ${DOCKERHUB_USERNAME} --password-stdin
 fi

.evergreen/start-docker-envs.sh

@@ -33,7 +33,7 @@ if [ "$HAS_DOCKER" = true ]; then
   docker version
   $DOCKER_COMPOSE version
 
-  if [ -z "$DOCKERHUB_PASSWORD" ]; then
+  if [ -n "$DOCKERHUB_PASSWORD" ]; then
     echo "Logging in to docker"
     echo "${DOCKERHUB_PASSWORD}" | docker login -u ${DOCKERHUB_USERNAME} --password-stdin
   fi