Rename BBufTest to BufTest

Motivation:
The BBufTest was implemented entirely in terms of the Buf interface.
There is no reason for it to reference any particular implementation.

Modification:
BBufTest and friends are renamed to just BufTest.

Result:
Tests are now named after the API surface they test.

buffer/src/test/java/io/netty/buffer/b2/BufTest.java

@@ -30,7 +30,7 @@ import java.util.concurrent.SynchronousQueue;
 import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 
-public abstract class BBufTest {
+public abstract class BufTest {
     protected abstract Allocator createAllocator();
 
     private Allocator allocator;

buffer/src/test/java/io/netty/buffer/b2/Codegen.java

@@ -571,7 +571,7 @@ public final class Codegen {
     public static void main(String[] args) throws Exception {
         generateCodeInline(Path.of("buffer/src/main/java/io/netty/buffer/b2/Buf.java"));
         generateCodeInline(Path.of("buffer/src/main/java/io/netty/buffer/b2/BBuf.java"));
-        generateCodeInline(Path.of("buffer/src/test/java/io/netty/buffer/b2/BBufTest.java"));
+        generateCodeInline(Path.of("buffer/src/test/java/io/netty/buffer/b2/BufTest.java"));
     }
 
     private static void generateCodeInline(Path path) throws IOException {

buffer/src/test/java/io/netty/buffer/b2/DirectBufTest.java

@@ -19,7 +19,7 @@ import org.junit.Test;
 
 import static org.junit.Assert.*;
 
-public class DirectBBufTest extends BBufTest {
+public class DirectBufTest extends BufTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.direct();

buffer/src/test/java/io/netty/buffer/b2/DirectBufWithCleanerTest.java

@@ -5,7 +5,7 @@ import org.junit.Test;
 import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 
-public class DirectBBufWithCleanerTest extends DirectBBufTest {
+public class DirectBufWithCleanerTest extends DirectBufTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.directWithCleaner();

buffer/src/test/java/io/netty/buffer/b2/HeapBufTest.java

@@ -19,7 +19,7 @@ import org.junit.Test;
 
 import static org.junit.Assert.*;
 
-public class HeapBBufTest extends BBufTest {
+public class HeapBufTest extends BufTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.heap();

buffer/src/test/java/io/netty/buffer/b2/PooledDirectBufTest.java

@@ -15,7 +15,7 @@
  */
 package io.netty.buffer.b2;
 
-public class PooledDirectBBufTest extends DirectBBufTest {
+public class PooledDirectBufTest extends DirectBufTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.pooledDirect();

buffer/src/test/java/io/netty/buffer/b2/PooledDirectBufWithCleanerTest.java

@@ -20,7 +20,7 @@ import org.junit.Test;
 import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.*;
 
-public class PooledDirectBBufWithCleanerTest extends DirectBBufWithCleanerTest {
+public class PooledDirectBufWithCleanerTest extends DirectBufWithCleanerTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.pooledDirectWithCleaner();

buffer/src/test/java/io/netty/buffer/b2/PooledHeapBufTest.java

@@ -15,7 +15,7 @@
  */
 package io.netty.buffer.b2;
 
-public class PooledHeapBBufTest extends HeapBBufTest {
+public class PooledHeapBufTest extends HeapBufTest {
     @Override
     protected Allocator createAllocator() {
         return Allocator.pooledHeap();