Update `@DynamicPropertySource` examples regarding changes in Testcontainers

[sbrannen]

While reviewing #29937, I realized that our Testcontainers examples are outdated: there is no longer a RedisContainer. Instead, a Redis container is configured via a GenericContainer, as documented in the official Testcontainers documentation.

[sbrannen]

@eddumelendez, I'd appreciate it if you could quickly review my changes in 8e9dc35 and confirm that our examples are up to date with the current APIs and recommendations for Testcontainers.

Thanks

[eddumelendez]

Hi @sbrannen ! I think for the example GenericContainer("redis:5.0.3-alpine") would be much better. DockerImageName is mostly used for Image name substitution when it is used along with Testcontainers modules such as MySQLContainer, PostgreSQLContainer and so on. getFirstMappedPort makes sense in this example 👍🏽

Thanks for updating docs related to Testcontainers :)

[sbrannen]

I think for the example GenericContainer("redis:5.0.3-alpine") would be much better. DockerImageName is mostly used for Image name substitution when it is used along with Testcontainers modules such as MySQLContainer, PostgreSQLContainer and so on.

Good to know. Thanks for the explanation.

FWIW, I based our examples on the examples provided at https://www.testcontainers.org/quickstart/junit_5_quickstart/.

getFirstMappedPort makes sense in this example 👍🏽

👍

Thanks for updating docs related to Testcontainers :)

Sure thing.

Reopening to address above suggestion.