build(deps): bump serialization from 1.5.1 to 1.7.3

Bumps `serialization` from 1.5.1 to 1.7.3.

Updates `org.jetbrains.kotlinx:kotlinx-serialization-core` from 1.5.1 to 1.7.3
- [Release notes](https://github.com/Kotlin/kotlinx.serialization/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.serialization/blob/master/CHANGELOG.md)
- [Commits](Kotlin/kotlinx.serialization@v1.5.1...v1.7.3)

Updates `org.jetbrains.kotlinx:kotlinx-serialization-json` from 1.5.1 to 1.7.3
- [Release notes](https://github.com/Kotlin/kotlinx.serialization/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.serialization/blob/master/CHANGELOG.md)
- [Commits](Kotlin/kotlinx.serialization@v1.5.1...v1.7.3)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlinx:kotlinx-serialization-core
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.jetbrains.kotlinx:kotlinx-serialization-json
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -66,7 +66,7 @@ robolectric = "4.12"
 runner = "1.0.2"
 rxandroid = "2.0.2"
 rxjava = "2.1.14"
-serialization = "1.5.1"
+serialization = "1.7.3"
 serialization-plugin = "1.8.22"
 slf4jNop = "2.0.9"
 spotless = "7.0.0.BETA3"