travis/run_tests.sh: set -ex; fix shellcheck issues (#170)
travis/run_tests.sh: set -ex; fix shellcheck issues (#170)


beniwohli/apm-agent-python,beniwohli/apm-agent-python,patrys/opbeat_python,patrys/opbeat_python,patrys/opbeat_python,beniwohli/apm-agent-python,beniwohli/apm-agent-python,patrys/opbeat_python