Coverage report not being uploaded to Codecov

[sschmidt23]

Bug report
I was reviewing the pyarrow PR and noticed that the usual codecov summary was missing. Looking at the Unit Tests and Coverage workflow, I see this error under the upload coverage report to codecov section:

[2024-05-23T13:35:49.321Z] ['error'] There was an error running the uploader: Error uploading to [https://codecov.io:](https://codecov.io/) Error: There was an error fetching the storage URL during POST: 429 - {'detail': ErrorDetail(string='Rate limit reached. Please upload with the Codecov repository upload token to resolve issue. Expected time to availability: 696s.', code='throttled')}

I also notice that this same error is present in the last merged branch to main, so it is not unique to the pyarrow PR. I'm not sure why this is failing, but probably worth tracking down.

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Please check the following:

• I have described the situation in which the bug arose, including what code was executed, information about my environment, and any applicable data others will need to reproduce the problem.
• I have included available evidence of the unexpected behavior (including error messages, screenshots, and/or plots) as well as a descriprion of what I expected instead.
• If I have a solution in mind, I have provided an explanation and/or pseudocode and/or task list.

[sschmidt23]

Could be an issue with the codecov token, maybe?