Spring Introduce placeholder resolution support in @ConcurrencyLimit

Commit c9078bfe1473040e8ded7259d42a98bf7deaa6a0 introduced placeholder resolution support for @Retryable attributes – for example, String maxAttemptsString() to complement the existing long maxAttempts() attribute.

Along the same lines, we should introduce placeholder resolution support for the value in @ConcurrencyLimit, so that concurrency throttling configuration can be externalized - for example, in a properties file.

Comment From: HyunSangHan

I submitted this PR #35470 :)