Bump up multipart test size

Author: bcully

test/framework/src/main/java/org/elasticsearch/repositories/AbstractThirdPartyRepositoryTestCase.java

@@ -291,7 +291,7 @@ public void testIndexLatest() throws Exception {
     public void testReadFromPositionWithLength() {
         final var blobName = randomIdentifier();
         // forcing multipart temporarily
-        final var blobBytes = randomBytesReference(randomIntBetween(5 * 1024 * 1024 + 100, 5 * 1024 * 1024 + 2_000));
+        final var blobBytes = randomBytesReference(randomIntBetween(25 * 1024 * 1024 + 100, 25 * 1024 * 1024 + 2_000));
 
         final var repository = getRepository();
         executeOnBlobStore(repository, blobStore -> {