travis: fix pull check

Signed-off-by: Ruslan Kuprieiev <[email protected]>

functest/test-import.sh

@@ -14,7 +14,7 @@ dvc_info "Import from http url"
 dvc import $DATA_S3/Tags.xml data/http
 dvc_check_files "data/http"
 
-if [ -z $TRAVIS_PULL_REQUEST ]; then
+if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then
 	dvc_info "Import from s3 url"
 	dvc config aws.region $REGION
 	dvc import s3://dataversioncontrol/functests/stackoverflow_raw_small/Tags.xml data/s3

functest/test-sync-aws.sh

@@ -4,7 +4,7 @@ set -e
 
 source common.sh
 
-if [ -z $TRAVIS_PULL_REQUEST ]; then
+if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then
 	dvc_create_repo
 
 	dvc_info "Setting up AWS cloud"