fix(rust): fix a printing issue in IR::Filter

[coastalwhite]

This resolves a small issue introduced by #16191, where the IR::Filter is printed incorrectly.

[codspeed-hq]

CodSpeed Performance Report

Merging #16378 will degrade performances by 19.01%

_{Comparing coastalwhite:fix-alp-format-filter-writeln (4306a3a) with main (2c4076e)}

Summary

❌ 1 regressions
✅ 36 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	coastalwhite:fix-alp-format-filter-writeln	Change
❌	test_tpch_q14	7.1 ms	8.8 ms	-19.01%

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.36%. Comparing base (2c4076e) to head (4306a3a).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16378      +/-   ##
==========================================
- Coverage   81.38%   81.36%   -0.03%     
==========================================
  Files        1406     1406              
  Lines      183909   183909              
  Branches     2953     2953              
==========================================
- Hits       149679   149642      -37     
- Misses      33717    33754      +37     
  Partials      513      513              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.