[clang-tools-extra] [clang-tidy] Update llvmlibc-implementation-in-namespace to new rules (PR #66504)

[Piotr Zegar via cfe-commits]

================
@@ -3,18 +3,18 @@
 #define MACRO_A "defining macros outside namespace is valid"
 
 class ClassB;
-// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: declaration must be declared within the '__llvm_libc' namespace
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: declaration must be declared within a namespace starting with '__llvm_libc'
 struct StructC {};
-// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: declaration must be declared within the '__llvm_libc' namespace
+// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: declaration must be declared within a namespace starting with '__llvm_libc'
 char *VarD = MACRO_A;
-// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: declaration must be declared within the '__llvm_libc' namespace
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: declaration must be declared within a namespace starting with '__llvm_libc'
 typedef int typeE;
-// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: declaration must be declared within the '__llvm_libc' namespace
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: declaration must be declared within a namespace starting with '__llvm_libc'
 void funcF() {}
-// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: declaration must be declared within the '__llvm_libc' namespace
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: declaration must be declared within a namespace starting with '__llvm_libc'
 
----------------
PiotrZSL wrote:

add test:

```
namespace outer_most {
 class A {}; // i think it wont provide warning 'declaration must be declared within a namespace starting with ' to A class
}
```

https://github.com/llvm/llvm-project/pull/66504