Fix Docker Hub build and deploy script to fail the job

[pmarques]

Description

Fail the TravisCI build if there is an error in the script _build_and_deploy_todockerhub.sh.

What I expected:

To install the missing version, run `gem install bundler:1.17.3`
    from /usr/local/lib/ruby/2.7.0/rubygems.rb:296:in `activate_bin_path'
    from /usr/local/bin/bundle:23:in `<main>'
The command '/bin/sh -c apk --update add --virtual build-dependencies build-base &&     bundle install &&     apk del build-dependencies build-base &&     rm -rf /var/cache/apk/*' returned a non-zero code: 1
The command "./build_and_deploy_to_dockerhub.sh" exited with 1.

Done. Your build exited with 1.

What happened:

Although the pipeline / job status reports success since the script is ignoring the errors.

The command '/bin/sh -c apk --update add --virtual build-dependencies build-base &&     bundle install &&     apk del build-dependencies build-base &&     rm -rf /var/cache/apk/*' returned a non-zero code: 1
The command "./build_and_deploy_to_dockerhub.sh" exited with 0.

Done. Your build exited with 0.

[claudijd]

Thanks @pmarques total oversight.