fix: update env vars to export (#60)

Author: anguillanneuf

.kokoro/build.sh

@@ -79,8 +79,8 @@ samples)
     if [[ -f ${SAMPLES_DIR}/pom.xml ]]
     then
       # get versions for constructing the full names of the packaged JARs
-      CONNECTOR_VERSION=$(grep pubsublite-spark-sql-streaming ${scriptDir}/../versions.txt | cut -d: -f3)
-      SAMPLE_VERSION=$(grep com.google.cloud.samples.shared-configuration: ${scriptDir}/../versions.txt | cut -d: -f3)
+      export CONNECTOR_VERSION=$(grep pubsublite-spark-sql-streaming ${scriptDir}/../versions.txt | cut -d: -f3)
+      export SAMPLE_VERSION=$(grep com.google.cloud.samples.shared-configuration: ${scriptDir}/../versions.txt | cut -d: -f3)
       if [ -f "${KOKORO_GFILE_DIR}/secret_manager/java-pubsublite-spark-samples-secrets" ]
         then
             source "${KOKORO_GFILE_DIR}/secret_manager/java-pubsublite-spark-samples-secrets"