Automatic rebaseline of codesize expectations. NFC (#24835)

This is an automatic change generated by
tools/maint/rebaseline_tests.py.

The following (1) test expectation files were updated by
running the tests with `--rebaseline`:

```
code_size/test_codesize_cxx_mangle.json: 258786 => 258785 [-1 bytes / -0.00%]

Average change: -0.00% (-0.00% - -0.00%)
```

Co-authored-by: emscripten-bot <[email protected]>

Author: github-actions[bot]

test/code_size/test_codesize_cxx_mangle.json

@@ -1,10 +1,10 @@
 {
   "a.out.js": 23460,
   "a.out.js.gz": 9162,
-  "a.out.nodebug.wasm": 235326,
-  "a.out.nodebug.wasm.gz": 78948,
-  "total": 258786,
-  "total_gz": 88110,
+  "a.out.nodebug.wasm": 235325,
+  "a.out.nodebug.wasm.gz": 78943,
+  "total": 258785,
+  "total_gz": 88105,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",