[MNT] Similarity search and RDST test failures in CI

[MatthewMiddlehurst]

Describe the issue

Similarity search and RDST are currently causing some errors in CI:

https://github.com/aeon-toolkit/aeon/actions/runs/10826946884/job/30039020141 https://github.com/aeon-toolkit/aeon/actions/runs/10863339134/job/30147372111 https://github.com/aeon-toolkit/aeon/actions/runs/10890837654/job/30220422286 https://github.com/aeon-toolkit/aeon/actions/runs/10910622966/job/30281472461 https://github.com/aeon-toolkit/aeon/actions/runs/10918273185/job/30303353216 (other failure here as well) https://github.com/aeon-toolkit/aeon/actions/runs/10918965119/job/30305612433

In case these expire, here are some examples:

FAILED aeon/testing/tests/test_all_estimators.py::test_all_estimators[check_fit_updates_state(estimator=RDSTRegressor(max_shapelets=20),datatype=EqualLengthUnivariate-Regression-np-list)] - ReferenceError: underlying object has vanished

FAILED aeon/similarity_search/distance_profiles/tests/test_naive_distance.py::test_normalized_naive_distance[dtw-float64] - ReferenceError: underlying object has vanished

I don't see any failures in numba disabled tests, but there is a low sample size.

Suggest a potential alternative/fix

Solve the case of the missing underlying object.

Additional context

Tests on general CI disabled by #2080