fix(python): Remove axis in show_graph

[mcrumiller]

Followup to #23210, which was merged a bit too quickly :)

Current:

New:

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 80.61%. Comparing base (171c847) to head (e985d29).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
py-polars/polars/_utils/various.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #23218   +/-   ##
=======================================
  Coverage   80.61%   80.61%           
=======================================
  Files        1639     1639           
  Lines      220007   220007           
  Branches     2814     2814           
=======================================
  Hits       177350   177350           
  Misses      41990    41990           
  Partials      667      667           

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.