build(deps): update cosign to v2.4.3

This MR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [cosign](https://github.com/sigstore/cosign) | patch | `2.4.2` -> `2.4.3` |

MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot).

**Proposed changes to behavior should be submitted there as MRs.**

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### Release Notes

<details>
<summary>sigstore/cosign (cosign)</summary>

### [`v2.4.3`](https://github.com/sigstore/cosign/blob/HEAD/CHANGELOG.md#v243)

[Compare Source](sigstore/cosign@v2.4.2...v2.4.3)

#### Features

-   Bump sigstore/sigstore to support KMS plugins ([#&#8203;4073](sigstore/cosign#4073))
-   Enable fetching signatures without remote get. ([#&#8203;4047](sigstore/cosign#4047))
-   Feat/file flag completion improvements ([#&#8203;4028](sigstore/cosign#4028))
-   Update builder to use go1.23.6 ([#&#8203;4052](sigstore/cosign#4052))

#### Bug Fixes

-   fix parsing error in --only for cosign copy ([#&#8203;4049](sigstore/cosign#4049))

#### Cleanup

-   Refactor verifyNewBundle into library function ([#&#8203;4013](sigstore/cosign#4013))
-   fix comment typo and imports order ([#&#8203;4061](sigstore/cosign#4061))
-   sync comment with parameter name in function signature ([#&#8203;4063](sigstore/cosign#4063))
-   sort properly Go imports ([#&#8203;4071](sigstore/cosign#4071))

#### Contributors

-   Bob Callaway
-   Carlos Tadeu Panato Junior
-   Cody Soyland
-   Dmitry Savintsev
-   Hayden B
-   Tomasz Janiszewski
-   Ville Skyttä

</details>

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This MR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Author: ECG Bot

chezmoi/dot_config/mise/config.toml

@@ -1,6 +1,6 @@
 [tools]
 aws-nuke = "latest"
-cosign = "2.4.2"
+cosign = "2.4.3"
 fd = "10.2.0"
 glab = "1.52.0"
 go = "1.24.0"