DOCS: update `delete_searchable_snapshot` option documentation (#71547)
DOCS: update `delete_searchable_snapshot` option documentation (#71547)

If enabled, the `delete_searchable_snapshot` option will attempt to delete the
index snapshot generated in any previous phase, for the purpose of mounting the
index as a searchable snapshot.

GlenRSmith/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,GlenRSmith/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch,robin13/elasticsearch,robin13/elasticsearch