Versions missing in requirements.txt

Having requirements.txt without versions is not stable.

Install is currently failing with:
```
warning: `VIRTUAL_ENV=labs/finops-framework/3.12` does not match the project environment path `.venv` and will be ignored
Resolved 271 packages in 184ms
warning: The package `urllib3==2.5.0` does not have an extra named `secure`
warning: The package `urllib3==2.5.0` does not have an extra named `secure`
error: Failed to prepare distributions
Caused by: Failed to fetch wheel: futures==3.4.0
Caused by: Build backend failed to determine extra requires with `build_wheel()` with exit status: 1
--- stdout:

--- stderr:
This backport is meant only for Python 2.
It does not work on Python 3, and Python 3 users do not need it as the concurrent.futures package is available in the standard library.
For projects that work on both Python 2 and 3, the dependency needs to be conditional on the Python version, like so:
extras_require={':python_version == "2.7"': ['futures']}
---
```