https://github.com/elastic/elasticsearch/pull/97304 removes several places that might do an expensive rebuild of the cluster state via `getStateForMasterService`. There's one other call we should be able to remove, in `JoinValidationService`, but it's a little tricky since we rely on seeing the last-accepted state for the cluster UUID validation, and it's not obviously ok to expose the last-accepted state without the no-master block.

This is a fairly minor issue because we do not do this join validation during elections, only if we're the elected master, and in that case `getStateForMasterService` is cheap. But that's not guaranteed, and we should strengthen this to avoid the that expensive step whenever possible.
server/src/main/java/org/elasticsearch/cluster/coordination/JoinValidationService.java
nextItem.onFailure(new NodeClosedException(transportService.getLocalNode()));
                }
            } while (queueSize.decrementAndGet() > 0);
        } catch (Exception e) {
            assert false : e;
            throw e;
        }
    }
    private final AbstractRunnable cacheClearer = new AbstractRunnable() {
        @Override
        public void onFailure(Exception e) {
            logger.error("unexpectedly failed to clear cache", e);
            assert false : e;
        }
        @Override
        protected void doRun() {
            
            
            for (final var bytes : statesByVersion.values()) {
                bytes.decRef();
            }
            statesByVersion.clear();
            logger.trace("join validation cache cleared");
        }
        @Override
        public String toString() {
            return "clear join validation cache";
        }
    };
    private class JoinValidation extends ActionRunnable<TransportResponse.Empty> {