Update test-coverage.yaml

[VisruthSK]

Summary

Fix codecov action

Copyright and Licensing

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license the submitted work under the following licenses:

• Code: BSD 3-clause (https://opensource.org/licenses/BSD-3-Clause)
• Documentation: CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if 32b8eaf is merged into master:

• ✔️as_draws_array: 143ms -> 143ms [-1.09%, +0.55%]
• ✔️as_draws_df: 69.1ms -> 68.5ms [-1.78%, +0.17%]
• ✔️as_draws_list: 155ms -> 155ms [-0.87%, +0.25%]
• ✔️as_draws_matrix: 24.5ms -> 24.7ms [-0.84%, +2.27%]
• ✔️as_draws_rvars: 114ms -> 114ms [-1.01%, +0.7%]
• ✔️summarise_draws_100_variables: 735ms -> 738ms [-0.13%, +0.71%]
• ✔️summarise_draws_10_variables: 82.6ms -> 82.4ms [-1.34%, +0.93%]
  Further explanation regarding interpretation and methodology can be found in the documentation.