Gpl: remove filler removal cap

[LucasYuki]

Issue #8477.

Removes the 10% limit of fillers cells removed during routability.

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[LucasYuki]

Summary of metrics across all design tests.

[maliberty]

I'm confused as the issue says

The current code should limit the maximum number of filler cells removed to 10%, but there is a bug that allows up to 100% of the filler cells to be removed.

but this is Removes the 10% limit of fillers. There is no such limit per the issue.

[gudeh]

As mentioned on a previous meeting we noticed it could be beneficial to remove the max cap filler removal, and allow for all fillers to be potentially removed.

Initially we wanted to remove at most 10% of the fillers. Although, there was a bug which we were accidentally removing all fillers, but even still this showed as a good outcome on some private designs, since after fixing the bug and removing only 10% of fillers showed congestion problems during GRT on private designs. By removing the max cap we see no divergences during GPL (on contrary to what I observed previously where multiple public designs were diverging consistently).

So we understand it would be better to instead of fixing the cap, just remove it. Since we do not see divergences and private designs benefit from removing the cap.

[maliberty]

Needs a small metric update
11:59:52 + ./test/regression jpeg_sky130hd
12:21:05 jpeg_sky130hd (tcl) FAIL GRT::ANT::errors 1 > 0

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[gudeh]

All green @maliberty