Fix fixtures that caused controller test to break

The job posting fixture was referencing a job_type foreign key of 3
which didnt exist in the test database. This adds a second (named)
fixture to the job_type.yml file and modifies the job_postings.yml
file so it uses that new ID.
Merge pull request #1 from mheisler1/bugfix/bph-fix-broken-controller-test

Fix fixtures that caused controller test to break