Move to clang-format 15 (#621)

The current version requires clang-format-9.  This now getting hard to get.
This commit moves it to the clang-format-15, which is the latest in 22.04.

Also, updates clang-tidy to 15 as well.

src/test/func/domestication/domestication.cc

@@ -62,14 +62,12 @@ namespace snmalloc
      * C++, and not just its initializer fragment, to initialize a non-prefix
      * subset of the flags (in any order, at that).
      */
-    static constexpr Flags Options = []() constexpr
-    {
+    static constexpr Flags Options = []() constexpr {
       Flags opts = {};
       opts.QueueHeadsAreTame = false;
       opts.HasDomesticate = true;
       return opts;
-    }
-    ();
+    }();
 
     static GlobalPoolState& pool()
     {

src/test/func/sandbox/sandbox.cc

@@ -172,7 +172,7 @@ namespace
        * sandbox but allocates memory inside.
        */
       struct RemoteAllocator queue;
-    } * shared_state;
+    }* shared_state;
 
     /**
      * The memory provider for this sandbox.
@@ -195,7 +195,7 @@ namespace
     Sandbox(size_t sb_size)
     : start(alloc_sandbox_heap(sb_size)),
       top(pointer_offset(start, sb_size)),
-      shared_state(new (start) SharedState()),
+      shared_state(new(start) SharedState()),
       state(
         pointer_offset(CapPtr<void, CBChunk>(start), sizeof(SharedState)),
         sb_size - sizeof(SharedState)),