Bump org.testcontainers:junit-jupiter in /springboot-app (#73)

Bumps [org.testcontainers:junit-jupiter](https://github.com/testcontainers/testcontainers-java) from 1.17.6 to 1.19.3.
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.17.6...1.19.3)

---
updated-dependencies:
- dependency-name: org.testcontainers:junit-jupiter
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

springboot-app/build.gradle.kts

@@ -35,7 +35,7 @@ dependencies {
   testImplementation("org.springframework.boot:spring-boot-starter-test")
   testImplementation("io.projectreactor:reactor-test")
 
-  testImplementation("org.testcontainers:junit-jupiter:1.17.6")
+  testImplementation("org.testcontainers:junit-jupiter:1.19.3")
   testImplementation("org.assertj:assertj-core:3.24.0")
 }