Fix ByteSizeValueTests.

This test had been using the version INITIAL_ELASTICSEARCH_9_0 as an example of
a version that used the older ByteSizeValue transport format. Now that no such
version exists anymore, it doesn't make sense to substitute a version that uses
the new format!

Author: prdoyle

server/src/test/java/org/elasticsearch/common/unit/ByteSizeValueTests.java

@@ -24,7 +24,6 @@
 
 import static org.elasticsearch.TransportVersions.BYTE_SIZE_VALUE_ALWAYS_USES_BYTES;
 import static org.elasticsearch.TransportVersions.V_8_16_0;
-import static org.elasticsearch.TransportVersions.V_9_0_0;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
@@ -523,7 +522,7 @@ protected void assertEqualInstances(ByteSizeValue expectedInstance, ByteSizeValu
 
     public void testBWCTransportFormat() throws IOException {
         var tenMegs = ByteSizeValue.ofMb(10);
-        for (var tv : List.of(V_8_16_0, V_9_0_0)) {
+        for (var tv : List.of(V_8_16_0)) {
             try (BytesStreamOutput expected = new BytesStreamOutput(); BytesStreamOutput actual = new BytesStreamOutput()) {
                 expected.writeZLong(10);
                 ByteSizeUnit.MB.writeTo(expected);