Without this change we don't even really know how many tags are created and what are their values.
With this change we want this information to be automatically rendered.
* Wraps producer / consumer once only
without this change we can wrap the kafka consumer / producer multiple times. First via post processors, second via aspect
with this change we're doing it only once via post processors. we do not wrap factories
fixes gh-1921
# Modules
* New modules: `spring-cloud-sleuth-autoconfigure`, `spring-cloud-sleuth-api`, `spring-cloud-sleuth-instrumentation`
`spring-cloud-sleuth-core` removed and changed to `spring-cloud-sleuth-instrumentation` & `spring-cloud-sleuth-api`
* Removed `spring-cloud-starter-sleuth-otel`
To add OpenTelemetry support you need to add `spring-cloud-starter-sleuth` (adds Brave by default), exclude Brave and add `spring-cloud-sleuth-otel` dependency
* Except for the tests, `spring-cloud-sleuth-autoconfigure` is the only module that can have access to `@Configuration`, `@ConfigurationProperties` classes.
Tests have been added to ensure such separation.
## Package moving
* `org.springframework.cloud.sleuth.api` -> `org.springframework.cloud.sleuth`
* `org.springframework.cloud.sleuth.brave.autoconfig` -> `org.springframework.cloud.sleuth.autoconfig.brave`
* `org.springframework.cloud.sleuth.otel.autoconfig` -> `org.springframework.cloud.sleuth.autoconfig.otel`
* `org.springframework.cloud.sleuth` -> `org.springframework.cloud.sleuth`
* Instrumentation: `org.springframework.cloud.sleuth.annotation` -> `org.springframework.cloud.sleuth.instrument.annotation`
* All the autoconfiguration classes were moved under `org.springframework.cloud/sleuth.autoconfig` package
## Global class modifications
* Any class registered as a bean is now public
## Classes
* `RateLimitingSampler` constructor changed
* Merged a lot of auto configuration classes into one (e.g. `BraveAutoConfiguration` now imports various other configurations)
* Renamed `TraceBraveAutoConfiguration` to `BraveAutoConfiguration`
* Renamed `TraceOtelAutoConfiguration` to `OtelAutoConfiguration`
* Removed all `NoOp` implementations of the API
