feat(input): show decimals if step is defined

[danielkaxis]

If attribute step is specified, show base values
together with decimals.

Describe your changes

By default a number input element is displaying integers without decimals when step is specified. To improve user experience and make it more clear that the input contains decimal values, show integers with the amount of decimals specified in the step attribute.

Issue ticket number and link

• Fixes NumberInput: Show integer values with decimals #237

Checklist before requesting a review

• I have performed a self-review of my own code
• I have verified that the code builds perfectly fine on my local system
• I have added tests that prove my fix is effective or that my feature works
• I have commented my code, particularly in hard-to-understand areas
• I have verified that my code follows the style already available in the repository
• I have made corresponding changes to the documentation

[danielkaxis]

Not sure why tests are failing, working fine locally.