Deprecate otelmongo/test (#5639)

Part of #5551

Follow up to a missing change not included in #5598. We want to
deprecate `otelmongo` and `otelmongo/test` at the same time.

instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/test/doc.go

@@ -7,5 +7,12 @@ Package test validates the otelmongo instrumentation with the default SDK.
 This package is in a separate module from the instrumentation it tests to
 isolate the dependency of the default SDK and not impose this as a transitive
 dependency for users.
+
+Deprecated: otelmongo has no Code Owner.
+After August 21, 2024, it may no longer be supported and may stop
+receiving new releases unless a new Code Owner is found. See
+[this issue] if you would like to become the Code Owner of this module.
+
+[this issue]: https://github.com/open-telemetry/opentelemetry-go-contrib/issues/5551
 */
 package test // import "go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/test"

instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/test/go.mod

@@ -1,3 +1,4 @@
+// Deprecated: otelmongo has no Code Owner.
 module go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/mongo/otelmongo/test
 
 go 1.21