[AIRFLOW-XXXX] Remove travis config warnings (#7467)
[AIRFLOW-XXXX] Remove travis config warnings (#7467)

Building on my fork on travis-ci.com I noticed that there is a new
config validation feature and these two things were giving warnings

(cherry picked from commit 3e5d272fcb9fefe35760590a767ba27be4d27665)

owlabs/incubator-airflow,owlabs/incubator-airflow,owlabs/incubator-airflow,owlabs/incubator-airflow