Implicit conversion from float-string to int is deprecated

[thisispiers]

See https://php.watch/versions/8.1/deprecate-implicit-conversion-incompatible-float-string

[nickbeen]

There is no explicit conversion of float-string to integer since number_format casts the percentage to a string. Are you trying to use the percentage value in your application?

[everton3x]

I got an error like this trying to use ProgressBar. All it took was to change the code of line 228 according to the change in the PR and everything started to work properly.

Any reason PR isn't merged yet?

[nickbeen]

This PR isn't merged yet, because:

1. There is no example (preferably with stack trace) of the notice provided
2. There is no test of this PR provided
3. This PR only touches setPercentage(); similar methods like setProgress() and setMaxProgress() may trigger the same notice
4. Other functionality may be affected like the console output

I'm working on a complete fix, so I'll merge this PR for now.