Update p025.py

[brayo-pip]

Runs faster, always prefer faster code I guess

[nayuki]

Rejected for these reasons:

• Uses floating-point algorithms without proof or justification.
• Uses docstring inappropriately.
• Fails to follow my code formatting style.
• Makes no practical improvement on speed, because I benchmarked my solution to run in under 0.1 second. https://www.nayuki.io/page/project-euler-solutions#benchmark-timings
• Violates some of my goals in Project Euler, such as:

I strongly avoid any floating-point arithmetic at all, unless there is no other reasonable way (that I know of) to solve the problem

( https://www.nayuki.io/page/project-euler-solutions )