Fixed pagination error in REST API's

[koolgax99]

Description

• Before, the new_page and prev_page field in the inputs API consisted links of /api/workflows. Now it is changed to /api/inputs.
• The offset param was set to NA50 in the next_page if it wasn't defined in the start for runs, workflows and inputs API.

Before

• For /api/inputs/ the response was: "next_page": "http://api.pecan.localhost:8000/api/workflows/NA50&limit=50"
• Similarly, For /api/workflows/ the response was: "next_page": "http://api.pecan.localhost:8000/api/workflows/NA50&limit=50"
• For /api/runs/ the response was: "next_page": "http://api.pecan.localhost:8000/api/runs/NA50&limit=50"

After

• For /api/inputs/ the response now is "next_page": "http://api.pecan.localhost:8000/api/inputs/?offset=50&limit=50"
• For /api/workflows/ the response now is "next_page": "http://api.pecan.localhost:8000/api/workflows/?offset=50&limit=50"
• For /api/runs/ the response now is "next_page": "http://api.pecan.localhost:8000/api/runs/?offset=50&limit=50"

Review Time Estimate

• [x] Immediately
• [ ] Within one week
• [ ] When possible

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [ ] My change requires a change to the documentation.
• [ ] My name is in the list of CITATION.cff
• [ ] I have updated the CHANGELOG.md.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.

[koolgax99]

@dlebauer sir i have added the changelog!