fix(common): Dropping CrossProcessLock must not release the lock if a CrossProcessGuard is still alive#6674

Hywan merged 5 commits into

matrix-org:mainmatrix-org/matrix-rust-sdk:mainfrom

Hywan:refactor-common-cross-process-lock-num_holdersHywan/matrix-rust-sdk:refactor-common-cross-process-lock-num_holdersCopy head branch name to clipboard