Replace `DockerImageNames` with a enum and relocate it from the
`testcontainers` to `container` package. The enum now also
becomes a common location that we can use to apply container
configuration such as timeouts.
Closes gh-41164
Co-authored-by: Phillip Webb <phil.webb@broadcom.com>
Remove `@ImportAutoConfiguration(SslAutoConfiguration.class)`, since
`SslAutoConfiguration.class` is already provided as an
auto-configuration with `@SpringBootTest`
See gh-35655
