Tests: Remove unused header includes

Tests/AK/TestBase64.cpp

@@ -7,7 +7,6 @@
 #include <LibTest/TestCase.h>
 
 #include <AK/Base64.h>
-#include <AK/ByteBuffer.h>
 #include <AK/String.h>
 #include <string.h>
 

Tests/AK/TestFind.cpp

@@ -8,7 +8,6 @@
 
 #include <AK/Array.h>
 #include <AK/Find.h>
-#include <AK/Vector.h>
 
 TEST_CASE(should_return_end_if_not_in_container)
 {

Tests/AK/TestJSON.cpp

@@ -7,7 +7,6 @@
 #include <LibTest/TestCase.h>
 
 #include <AK/HashMap.h>
-#include <AK/JsonArray.h>
 #include <AK/JsonObject.h>
 #include <AK/JsonValue.h>
 #include <AK/String.h>

Tests/AK/TestQuickSort.cpp

@@ -6,7 +6,6 @@
 
 #include <LibTest/TestCase.h>
 
-#include <AK/Checked.h>
 #include <AK/Noncopyable.h>
 #include <AK/QuickSort.h>
 #include <AK/StdLibExtras.h>

Tests/AK/TestUFixedBigInt.cpp

@@ -11,8 +11,6 @@
 #include <AK/Random.h>
 #include <AK/UFixedBigInt.h>
 
-#include <time.h>
-
 constexpr int test_iterations = 32;
 
 TEST_CASE(one_plus_one)