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/metrics/InternalGeoCentroidTests.java
double lonSum = 0;
        double latSum = 0;
        long totalCount = 0;
        for (InternalGeoCentroid input : inputs) {
            if (input.count() > 0) {
                lonSum += (input.count() * input.centroid().getLon());
                latSum += (input.count() * input.centroid().getLat());
            }
            totalCount += input.count();
        }
        if (totalCount > 0) {
            assertEquals(latSum / totalCount, reduced.centroid().getLat(), 1E-5D);
            assertEquals(lonSum / totalCount, reduced.centroid().getLon(), 1E-5D);
        }
        assertEquals(totalCount, reduced.count());
    }
    @Override
    protected boolean supportsSampling() {
        return true;
    }
    @Override
    protected void assertSampled(InternalGeoCentroid sampled, InternalGeoCentroid reduced, SamplingContext samplingContext) {
        assertEquals(sampled.centroid().getLat(), reduced.centroid().getLat(), 1e-12);
        assertEquals(sampled.centroid().getLon(), reduced.centroid().getLon(), 1e-12);
        assertEquals(sampled.count(), samplingContext.scaleUp(reduced.count()), 0);
    }
    public void testReduceMaxCount() {
        InternalGeoCentroid maxValueGeoCentroid = new InternalGeoCentroid(
            "agg",
            new GeoPoint(10, 0),