PPF-750: Improve Integer and Float Input Handling in PdfWrapper.fill() Method

[alexperedel]

All Submissions:

• [x] Have you followed the guidelines in the developer guide?
• [x] Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Feature Submissions:

1. [x] Does your submission pass tests?
2. [x] Have you lint your code locally prior to submission?

Changes to Core Features:

• [x] Have you added an explanation of what your changes do and why you'd like us to include them?
• [x] Have you written new tests for your core changes, as applicable?
• [x] Have you successfully ran tests with your changes locally?

[alexperedel]

@chinapandaman Could you please review this PR when you have time?