Update module github.com/prometheus/client_golang to v1.20.4

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
github.com/prometheus/client_golang	v1.20.3 -> v1.20.4

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[!WARNING] Some dependencies could not be looked up. Check the Dependency Dashboard for more information.

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Release Notes

prometheus/client_golang (github.com/prometheus/client_golang)

### [`v1.20.4`](https://redirect.github.com/prometheus/client_golang/releases/tag/v1.20.4) [Compare Source](https://redirect.github.com/prometheus/client_golang/compare/v1.20.3...v1.20.4) - \[BUGFIX] histograms: Fix a possible data race when appending exemplars vs metrics gather. [#​1623](https://redirect.github.com/prometheus/client_golang/issues/1623)

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Configuration

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 89.34%. Comparing base (b8c64df) to head (4d9a75d). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2564 +/- ## ======================================= Coverage 89.34% 89.34% ======================================= Files 100 100 Lines 7630 7630 Branches 50 50 ======================================= Hits 6817 6817 Misses 756 756 Partials 57 57 ```

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