fix join non matching table

[melonora]

Currently, matching an element to non matching table (sliced table) can fail when match_rows is not no.

For example on main this would fail:

from spatialdata.datasets import blobs_annotating_element
from spatialdata import join_spatialelement_

sdata = blobs_annotating_element("blobs_circles")
sdata['table'] = sdata['table'][:3]
el, table = join_spatialelement_table(sdata, spatial_element_names="blobs_circles", table_name="table", how="inner", match_rows="left")

This PR fixes that issue.

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 1 line in your changes missing coverage. Please review.

Project coverage is 91.80%. Comparing base (7fc5eb4) to head (7a57b9b).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
src/spatialdata/_core/query/relational_query.py	94.44%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #813      +/-   ##
==========================================
+ Coverage   91.79%   91.80%   +0.01%     
==========================================
  Files          45       45              
  Lines        7055     7064       +9     
==========================================
+ Hits         6476     6485       +9     
  Misses        579      579              

Files with missing lines	Coverage Δ
src/spatialdata/_core/query/relational_query.py	90.66% <94.44%> (+0.19%)	⬆️