Update module prometheus/client_golang to v1.9.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
github.com/prometheus/client_golang	require	minor	v1.8.0 -> v1.9.0

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Release Notes

prometheus/client_golang

### [`v1.9.0`](https://togithub.com/prometheus/client_golang/releases/v1.9.0) [Compare Source](https://togithub.com/prometheus/client_golang/compare/v1.8.0...v1.9.0) - [FEATURE] `NewPidFileFn` helper to create process collectors for processes whose PID is read from a file. [#​804](https://togithub.com/prometheus/client_golang/issues/804) - [BUGFIX] promhttp: Prevent endless loop in `InstrumentHandler...` middlewares with invalid metric or label names. [#​823](https://togithub.com/prometheus/client_golang/issues/823)

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