Remove nextest filtration (#3885)

Fixes
https://github.com/paritytech/polkadot-sdk/issues/3884#issuecomment-2026058687

After moving regression tests to benchmarks
(https://github.com/paritytech/polkadot-sdk/pull/3741) we don't need to
filter tests anymore.

---------

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>
Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>
Co-authored-by: Alin Dima <alin@parity.io>
Co-authored-by: Andrei Sandu <andrei-mihail@parity.io>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Javier Viola <363911+pepoviola@users.noreply.github.com>
Co-authored-by: Serban Iorga <serban@parity.io>
Co-authored-by: Adrian Catangiu <adrian@parity.io>
Co-authored-by: Bastian Köcher <git@kchr.de>
Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>
Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>
Co-authored-by: Dastan <88332432+dastansam@users.noreply.github.com>
Co-authored-by: Liam Aharon <liam.aharon@hotmail.com>
Co-authored-by: Clara van Staden <claravanstaden64@gmail.com>
Co-authored-by: Ron <yrong1997@gmail.com>
Co-authored-by: Vincent Geddes <vincent@snowfork.com>
Co-authored-by: Svyatoslav Nikolsky <svyatonik@gmail.com>
Co-authored-by: Bastian Köcher <info@kchr.de>