Add an ability to resolve property placeholders in `BasicPersistentEntity`

[timsazon]

It'd be nice to have the ability to resolve placeholders in the entity values.

It can be done by adding PropertyResolver to the entity class.

[mp911de]

Can we take a step back first to understand what you're trying to achieve? Specifically, in Spring Data KeyValue we have support for SpEL expressions that are much more powerful than property resolution.

[timsazon]

I want to use application properties placeholders in @KeySpace and @RedisHash annotations, but afaik SpEL expressions can't handle it. For example, @EnableRedisWebSession annotation from Spring Session Data Redis supports such placeholders for namespaces.
You can see a use case in the test: https://github.com/spring-projects/spring-data-keyvalue/pull/375/files#diff-3894631e2abde2a85bfbe3ff79c5eb88c4388932ad2d25907cf0f02d8bf6cbc6R70

[mp911de]

Take a look at this example. It's built on top of Spring Data KeyValue and by providing an EvaluationContextExtension you can expose properties that can be resolved/accessed already.

[timsazon]

In that case, it will require additional configuration. I think it'd be better to support this the same way as @Value or @EnableRedisWebSession do (it doesn't change API anyway).