update travis to use postgres branch of sensu-go-bonsai-asset tooling

Author: Cameron Johnston

.travis.yml

@@ -25,7 +25,7 @@ script:
 - gem build sensu-plugins-postgres.gemspec
 - gem install sensu-plugins-postgres-*.gem
 before_deploy:
-- bash -c "[ ! -d bonsai/ ] && git clone https://github.com/sensu/sensu-go-bonsai-asset.git bonsai || echo 'bonsai/ exists, skipping git clone'"
+- bash -c "[ ! -d bonsai/ ] && git clone https://github.com/sensu/sensu-go-bonsai-asset.git --branch postgres --single-branch bonsai || echo 'bonsai/ exists, skipping git clone'"
 deploy:
 - provider: rubygems
   api_key:
@@ -37,7 +37,7 @@ deploy:
     rvm: 2.4.1
     repo: sensu-plugins/sensu-plugins-postgres
 - provider: script
-  script: bonsai/ruby-runtime/travis-build-ruby-plugin-assets.sh sensu-plugins-postgres
+  script: bonsai/ruby-runtime/travis-build-ruby-plugin-postgres-assets.sh sensu-plugins-postgres
   skip_cleanup: true
   on:
     tags: true