Supported languages tests

[archx3]

Summary / Highlights

Added integration test for the supported languages endpoints

Details (Give details about what this PR accomplishes, include any screenshots etc)

Testing Steps (Provide details on how your changes can be tested)

Requirements (place an x in each [ ] to check a box)

What kind of change does this PR introduce? (check at least one)

• [x] Bugfix

• [ ] Feature

• [ ] Performance improvement

• [ ] Feature removal

• [ ] Code style update

• [x] Refactor

• [ ] Docs

• [ ] Build-related changes

• [x] Other, please describe:

• [x] I've read and understood the Contributing Guidelines and have done my best effort to follow them.

• [x] I've tested my changes manually.

• [ ] I've added unit tests to my PR.

Transparency (Project board)

• [x] It's submitted to a feature branch, not the main branch

• [x] I've given my PR a meaningful title.

• [ ] I linked this PR to the relevant issue.

• [ ] I moved the linked issue from the "Sprint backlog" to "In progress" when I started this.

• [ ] I moved the linked issue to "QA Verification" now that it is ready to merge.

• [x] All tests are passing: https://github.com/massenergize/massenergize-campaigns/blob/main/.github/CONTRIBUTING.md#development-setup

• [x] New/updated tests are included