* Fix multi.exec with empty queue and previous watch
When calling exec on a multi instance which you did not use, no command is sent currently.
This is a problem for watched keys, because no EXEC means no unwatch, which might cause hard-to-debug problems.
Proposed Fix: Sending UNWATCH
* execute empty multi command (instead of skipping)
* Update index.ts
* Update index.ts
* Update multi-command.ts
* Update multi-command.ts
* Update multi-command.ts
* Update multi-command.ts
* short circuit empty pipelines
* Update index.ts
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Co-authored-by: Leibale <me@leibale.com>
