build: upgrade to C++23

Meson 1.1.1 and GCC-13 both support C++23 and a sufficient portion of
the standard has been implemented.  Upgrade the build to leverage it.

Change-Id: I67ac75516840d1c59978045e37669fd6ff57273d
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/meson.build b/meson.build
index 5549302..3ac77a5 100644
--- a/meson.build
+++ b/meson.build
@@ -6,7 +6,7 @@
     default_options: [
         'b_ndebug=if-release',
         'cpp_rtti=false',
-        'cpp_std=c++20',
+        'cpp_std=c++23',
         'warning_level=3',
         'werror=true',
     ],