Resolves#7894
Replace `MethodHandle` with older `java.lang.reflect.Field`, which is
supported on older Java versions.
Also enables animal sniffer for the RxJava2 instrumentation to prevent
regression.
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Co-authored-by: opentelemetrybot <107717825+opentelemetrybot@users.noreply.github.com>
* Move async strategies to annotation support
* Fix dependencies and refactor copypasta
* Move AsyncSpanEndStrategy to annotation support project
* spotless