This commit reverts most of #33157 as it introduces another race
condition and breaks a common case of watcher, when the first watch is
added to the system and the index does not exist yet.
This means, that the index will be created, which triggers a reload, but
during this time the put watch operation that triggered this is not yet
indexed, so that both processes finish roughly add the same time and
should not overwrite each other but act complementary.
This commit reverts the logic of cleaning out the ticker engine watches
on start up, as this is done already when the execution is paused -
which also gets paused on the cluster state listener again, as we can be
sure here, that the watches index has not yet been created.
This also adds a new test, that starts a one node cluster and emulates
the case of a non existing watches index and a watch being added, which
should result in proper execution.
Closes#33320
1de2a925ce