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
DateFieldMapper.Resolution.MILLISECONDS
        );
        private final List<InternalAggregation> results = new ArrayList<>();
        private final List<InternalAutoDateHistogram.Bucket> buckets = new ArrayList<>();
        private final int targetBuckets;
        ReduceTestBuilder(int targetBuckets) {
            this.targetBuckets = targetBuckets;
        }
        ReduceTestBuilder bucket(String key, long docCount) {
            buckets.add(new InternalAutoDateHistogram.Bucket(utcMillis(key), docCount, FORMAT, InternalAggregations.EMPTY));
            return this;
        }
        ReduceTestBuilder finishShardResult(String whichRounding, int innerInterval) {
            RoundingInfo roundings[] = AutoDateHistogramAggregationBuilder.buildRoundings(ZoneOffset.UTC, null);
            int roundingIdx = -1;
            for (int i = 0; i < roundings.length; i++) {
                if (roundings[i].unitAbbreviation.equals(whichRounding)) {
                    roundingIdx = i;
                    break;
                }
            }
            assertThat("rounding [" + whichRounding + "] should be in " + Arrays.toString(roundings), roundingIdx, greaterThan(-1));
            assertTrue(
                Arrays.toString(roundings[roundingIdx].innerIntervals) + " must contain " + innerInterval,
                Arrays.binarySearch(roundings[roundingIdx].innerIntervals, innerInterval) >= 0
            );
            BucketInfo bucketInfo = new BucketInfo(roundings, roundingIdx, InternalAggregations.EMPTY);
            results.add(
                new InternalAutoDateHistogram(
                    "test",