Fixes#15817
This commit addresses several data-races on the `tsm1.Predicate` type
that were causing a live-lock or similar in rare cases during a delete.
Because `tsm1/FileStore.Apply` executes concurrently across TSM files
the state of the delete's predicate was being unsafely mutated.
This commit adds a `Clone` method to the `influxdb.Predicate` type,
which should be used whenever an `influxdb.Predicate` implementation
needs to be used concurrently.
Edd Robinson
Kelvin Wang