`stats_agg::tests::pg_stats_agg_fuzz` is flakky

[surister]

Happens in CI and locally:

Client Error:
Output didn't match between postgres command: SELECT regr_intercept(test_y, test_x)::float, (SELECT regr_intercept(test_y, test_x) OVER (ORDER BY test_x ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) FROM test_table LIMIT 1 OFFSET 3)::float FROM test_table                                                                                                                                                                                                                 
and stats_agg command: SELECT intercept(stats_agg(test_y, test_x))::float, (stats_agg(test_y, test_x)->intercept())::float, intercept((SELECT stats_agg(test_y, test_x) OVER (ORDER BY test_x ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) FROM test_table LIMIT 1 OFFSET 3))::float FROM test_table                                                                                                                                                                           
        postgres result: 648237.0965988464                                                                                                                                                                                            
        statsagg result: 648237.096598847                                                                                                                                                                                             
        relative difference:         0.0000000000000008979378258182045                                                                                                                                                                
        allowed relative difference: 0.0000000000000002220446049250313                                                                                                                                                                
Failed after 3 successful iterations, run using 10000 values generated from seed 14705134910594273637                                                                                                                                 
postgres location: stats_agg.rs:1719
rust location: <unknown>

[Dvdandrades]

Same issue:

Client Error:
Output didn't match between postgres command: SELECT regr_intercept(test_y, test_x)::float, (SELECT regr_intercept(test_y, test_x) OVER (ORDER BY test_x ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) FROM test_table LIMIT 1 OFFSET 3)::float FROM test_table
and stats_agg command: SELECT intercept(stats_agg(test_y, test_x))::float, (stats_agg(test_y, test_x)->intercept())::float, intercept((SELECT stats_agg(test_y, test_x) OVER (ORDER BY test_x ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) FROM test_table LIMIT 1 OFFSET 3))::float FROM test_table 
	postgres result: 3792954.318155188
	statsagg result: 3792954.318155187
	relative difference:         0.00000000000000024554015063077635
	allowed relative difference: 0.0000000000000002220446049250313
Failed after 3 successful iterations, run using 10000 values generated from seed 6365590097639049054
postgres location: stats_agg.rs:1859
rust location: <unknown>

[surister]

https://github.com/timescale/timescaledb-toolkit/actions/runs/30262021293/job/89963903592?pr=952