Oldest tests: use a fixed pandas version

[markotoplak]

No description provided.

[codecov-commenter]

Codecov Report

Attention: 149 lines in your changes are missing coverage. Please review.

Comparison is base (5ef0d45) 33.92% compared to head (f530d18) 36.03%.
Report is 14 commits behind head on master.

Files	Patch %	Lines
orangecontrib/prototypes/widgets/owchatgptbase.py	0.00%	108 Missing ⚠️
orangecontrib/prototypes/widgets/owchatgpt.py	0.00%	20 Missing ⚠️
...contrib/prototypes/widgets/owchatgptconstructor.py	0.00%	18 Missing ⚠️
...rangecontrib/prototypes/widgets/owtexttocolumns.py	93.02%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #265      +/-   ##
==========================================
+ Coverage   33.92%   36.03%   +2.11%     
==========================================
  Files           9       11       +2     
  Lines        1515     1479      -36     
==========================================
+ Hits          514      533      +19     
+ Misses       1001      946      -55     

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