cert-manager: update Helm release cert-manager to v1.15.3

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cert-manager (source)	HelmChart	patch	v1.15.2 -> v1.15.3

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Release Notes

cert-manager/cert-manager (cert-manager)

### [`v1.15.3`](https://togithub.com/cert-manager/cert-manager/compare/v1.15.2...v1.15.3) [Compare Source](https://togithub.com/cert-manager/cert-manager/compare/v1.15.2...v1.15.3)

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