Swapped Pool Size to be managed in Spring Properties

[Crain-32]

Description of changes:

• Swapped hardcoded value to be a Spring Property

You can validate the pool size being set by using the follow breakpoints.
TaskSchedulingConfigurations.TaskSchedulerBuilderConfiguration::taskSchedulerBuilder sets the builder from the properties.
TaskSchedulingConfigurations.TaskSchedulerConfiguration::taskScheduler builds your ThreadPoolTaskScheduler using that builder.

A similar swap can be done for your CaffeineCacheManager, which you can dig into here. Which can be beneficial for testing where your MockCacheManager can instead just be spring.cache.type=SIMPLE

[CLAassistant]

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