include/octomap/math/Vector3.h:268:5: warning: non-void function does not return a value in all control paths [-Wreturn-type]

QA warning with clang-19 :
```
In file included from octomap-1.10.0/octomap/src/math/Vector3.cpp:34:
octomap-1.10.0/octomap/include/octomap/math/Vector3.h:268:5: warning: non-void function does not return a value in all control paths [-Wreturn-type]
  268 |     }
      |     ^
```