frontend: Auto release OBS data objects

[cg2121]

Description

These obs_data_t objects were still being manually released.

Motivation and Context

Cleaner code

How Has This Been Tested?

Ran OBS and made sure everything still worked.

Types of changes

• Code cleanup (non-breaking change which makes code smaller or more readable)

Checklist:

• I have read the contributing document.
• My code has been run through clang-format.
• My code follows the project's style guidelines
• My code is not on the master branch.
• My code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.