build(deps): bump io.micronaut.platform:micronaut-parent (#798)

Bumps [io.micronaut.platform:micronaut-parent](https://github.com/micronaut-projects/micronaut-core) from 4.7.1 to 4.7.3.
- [Release notes](https://github.com/micronaut-projects/micronaut-core/releases)
- [Changelog](https://github.com/micronaut-projects/micronaut-core/blob/4.8.x/RELEASE.adoc)
- [Commits](micronaut-projects/micronaut-core@v4.7.1...v4.7.3)

---
updated-dependencies:
- dependency-name: io.micronaut.platform:micronaut-parent
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]

gradle/libs.versions.toml

@@ -1,5 +1,5 @@
 [versions]
-micronautPlatform = "4.7.1"
+micronautPlatform = "4.7.3"
 kotlin = "2.1.0"
 jackson = "2.18.2"
 kotest = "5.9.1"