Release v1.64.1

This is release 1.64.1 (grateful) of gRPC Core.

For gRPC documentation, see grpc.io. For previous releases, see Releases.

This release contains refinements, improvements, and bug fixes, with highlights listed below.

Core

• [StatsPlugin] Fix use-after-free issue (#36664). (#36670)

C++

• [OTel] Generate pkg-config file for grpcpp_otel_plugin (#36686). (#36722)
• [OTel] Add find_package call for OTel dependency in installed gRPC configuration (#36674). (#36688)

Python

• [Python Server] Remove abstractmethod notation for add_registered_method_handlers (v1.64.x backport). (#36696)