The following aggregation tests all contain switch statements with branches that will never execute. The tests use a `between(x, y)` switch expression, but there are `case` values that are outside the randomised range. We need to fix these before #88739 can be merged. By "fix", I mean either remove the spurious cases, or if we actually want them, then extend the randomized range.

   * InternalAutoDateHistogramTests
   * InternalAvgTests
   * InternalDerivativeTests
   * InternalGeoCentroidTests
   * InternalWeightedAvgTests
   * SignificantLongTermsTests
   * SignificantStringTermsTests
server/src/test/java/org/elasticsearch/search/aggregations/bucket/histogram/InternalAutoDateHistogramTests.java
for (Histogram.Bucket bucket : histogram.getBuckets()) {
                        long roundedBucketKey = prepared.round(((ZonedDateTime) bucket.getKey()).toInstant().toEpochMilli());
                        long docCount = bucket.getDocCount();
                        if (roundedBucketKey >= keyForBucket && roundedBucketKey < nextKey) {
                            expectedCounts.compute(key, (k, oldValue) -> (oldValue == null ? 0 : oldValue) + docCount);
                        }
                    }
                }
                keyForBucket = nextKey;
            }
            
            
            if (prepared.round(lowest) == prepared.round(highest) && expectedCounts.isEmpty()) {
                expectedCounts.put(Instant.ofEpochMilli(prepared.round(lowest)), 0L);
            }
        }
        
        Map<Instant, Long> actualCounts = new TreeMap<>();
        for (Histogram.Bucket bucket : reduced.getBuckets()) {
            actualCounts.compute(
                ((ZonedDateTime) bucket.getKey()).toInstant(),
                (key, oldValue) -> (oldValue == null ? 0 : oldValue) + bucket.getDocCount()
            );
        }
        assertEquals(expectedCounts, actualCounts);
        DateHistogramInterval expectedInterval;
        if (reduced.getBuckets().size() == 1) {
            expectedInterval = reduced.getInterval();
        } else {
            expectedInterval = new DateHistogramInterval(innerIntervalToUse + roundingInfo.unitAbbreviation);