Today we log a "deleting snapshots [...] from repository [...]" message at INFO level [almost the first thing](https://github.com/elastic/elasticsearch/blob/dfaec0dbf0c8a0ba2912381334019725848f1f5a/server/src/main/java/org/elasticsearch/snapshots/SnapshotsService.java#L1886-L1888) when we start the deletion. However, the requested snapshots may not exist or they may be wildcards to be matched against actual snapshots. In these cases, the log message is either misleading or insuffiicent. Instead we should log the message after we have successfully added the delete to the cluster state similar to how the [logging works for snapshot creation](https://github.com/elastic/elasticsearch/blob/f77c16b78bab5e9f3ee24974aeba408e254e8c94/server/src/main/java/org/elasticsearch/snapshots/SnapshotsService.java#L3804).
server/src/main/java/org/elasticsearch/snapshots/SnapshotsService.java
final Exception e = new NotMasterException("no longer master");
                    for (String delete : Set.copyOf(snapshotDeletionListeners.keySet())) {
                        failListenersIgnoringException(snapshotDeletionListeners.remove(delete), e);
                    }
                }
            }
        } catch (Exception e) {
            assert false : new AssertionError(e);
            logger.warn("Failed to update snapshot state ", e);
        }
        assert assertConsistentWithClusterState(event.state());
        assert assertNoDanglingSnapshots(event.state());
    }
    private boolean assertConsistentWithClusterState(ClusterState state) {
        final SnapshotsInProgress snapshotsInProgress = SnapshotsInProgress.get(state);
        if (snapshotsInProgress.isEmpty() == false) {
            synchronized (endingSnapshots) {
                final Set<Snapshot> runningSnapshots = Stream.concat(
                    snapshotsInProgress.asStream().map(SnapshotsInProgress.Entry::snapshot),
                    endingSnapshots.stream()
                ).collect(Collectors.toSet());
                final Set<Snapshot> snapshotListenerKeys = snapshotCompletionListeners.keySet();
                assert runningSnapshots.containsAll(snapshotListenerKeys)
                    : "Saw completion listeners for unknown snapshots in "
                        + snapshotListenerKeys
                        + " but running snapshots are "
                        + runningSnapshots;
            }
        }
        final SnapshotDeletionsInProgress snapshotDeletionsInProgress = SnapshotDeletionsInProgress.get(state);