[ECM] fix FindCanberra for static builds

[wrobelda]

Also remove dangling do-not-override-custom-clang-format-files.patch

• What does your PR fix?

  Provides a static build fix for [kf5notifications] new port #19828, [kf5declarative] new port #19813

• Which triplets are supported/not supported? Have you updated the CI baseline?

  No change

• Does your PR follow the maintainer guide?

  Yes

• If you have added/updated a port: Have you run ./vcpkg x-add-version --all and committed the result?

  Yes

[github-actions]

You have modified or added at least one portfile where deprecated functions are used.

If you feel able to do so, please consider migrating them to the new functions:
vcpkg_install_cmake -> vcpkg_cmake_install (from port vcpkg-cmake)
vcpkg_build_cmake -> vcpkg_cmake_build (from port vcpkg-cmake)
vcpkg_configure_cmake -> vcpkg_cmake_configure (Please remove the option PREFER_NINJA) (from port vcpkg-cmake)
vcpkg_fixup_cmake_targets -> vcpkg_cmake_config_fixup (from port vcpkg-cmake-config)

In the ports that use the new function, you have to add the corresponding dependencies:

{
  "name": "vcpkg-cmake",
  "host": true
},
{
  "name": "vcpkg-cmake-config",
  "host": true
}

The following files are affected:

• ports/ecm/portfile.cmake

[BillyONeal]

Thanks for the fix!