Update Tax and NI Contributions for 2025

Description

I have noticed that percentages are changed for 2025, so we need to update percentages and salary limits for 2025. As 2024 is not visible in TABLE_A_EMPLOYER_NIC we should add it same as 2023. https://www.gov.uk/guidance/rates-and-thresholds-for-employers-2025-to-2026#paye-tax-and-class-1-national-insurance-contributions is a source to retrieve the new percentages for 2025.

Acceptance criteria

1. Add 2024 as 2023 in the table.
2. Add 2025 using the link provided and tag the new version. Don't forget to update the version in setup.py.
3. Update salaries-commitments repo with new salaries package and release.
4. Update webapp repo with the new salaries package and release.