AK+Everywhere: Rename String to DeprecatedString

We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)

Userland/Libraries/LibJS/Bytecode/BasicBlock.cpp

@@ -4,19 +4,19 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include <AK/String.h>
+#include <AK/DeprecatedString.h>
 #include <LibJS/Bytecode/BasicBlock.h>
 #include <LibJS/Bytecode/Op.h>
 #include <sys/mman.h>
 
 namespace JS::Bytecode {
 
-NonnullOwnPtr<BasicBlock> BasicBlock::create(String name, size_t size)
+NonnullOwnPtr<BasicBlock> BasicBlock::create(DeprecatedString name, size_t size)
 {
     return adopt_own(*new BasicBlock(move(name), max(size, static_cast<size_t>(4 * KiB))));
 }
 
-BasicBlock::BasicBlock(String name, size_t size)
+BasicBlock::BasicBlock(DeprecatedString name, size_t size)
     : m_name(move(name))
 {
     // FIXME: This is not the smartest solution ever. Find something cleverer!