update the INSTALL doc to referece the trace target instead of the interface sdk target and add note about potential move of the etw and elasticsearch components (open-telemetry#3422)

Author: dbarker

INSTALL.md

@@ -221,13 +221,17 @@ target_link_libraries(foo_lib PRIVATE opentelemetry-cpp::api)
 # foo_app/CMakeLists.txt
 find_package(opentelemetry-cpp CONFIG REQUIRED COMPONENTS api sdk exporters_otlp_grpc)
 add_executable(foo_app main.cpp)
-target_link_libraries(foo_app PRIVATE foo_lib opentelemetry-cpp::api opentelemetry-cpp::sdk opentelemetry-cpp::otlp_grpc_exporter )
+target_link_libraries(foo_app PRIVATE foo_lib opentelemetry-cpp::api opentelemetry-cpp::trace opentelemetry-cpp::otlp_grpc_exporter )
 ```
 
 The following table provides the mapping between components and targets. Components
 and targets available in the installation depends on the opentelemetry-cpp package
 build configuration.
 
+> **Note:** components `exporters_elasticsearch` and `exporters_etw`
+ may be moved out of the core package and to `opentelemetry-cpp-contrib`
+  in a future release
+
 | Component                  | Targets                                                                                          |
 |----------------------------|--------------------------------------------------------------------------------------------------|
 | **api**                    | opentelemetry-cpp::api                                                                           |