The previous implementation initialized the version number only once.
This caused subsequent calls to wxWebView::GetBackendVersionInfo() to
return the same version number even if the runtime has been updated or
a fixed version runtime had been activated via
wxWebViewEdge::MSWSetBrowserExecutableDir().
This change allows to require a minimum runtime version and allow
a runtime update without requiring a restart of the application.
Closes#22076.
03efe56cf9