Spurious dependency on utf8cpp imported target in assimp CMake imported target

[traversaro]

Describe the bug
Since #13521, the assimp CMake config file contain a transitive dependency to the utf8cpp imported target

Environment

• OS: Windows
• Compiler: Not relevant

To Reproduce
Steps to reproduce the behavior:

1. ./vcpkg install assimp
2. Inspect the assimp cmake config file, you will see:

# Create imported target assimp::assimp
add_library(assimp::assimp SHARED IMPORTED)

set_target_properties(assimp::assimp PROPERTIES
  INTERFACE_INCLUDE_DIRECTORIES "${_IMPORT_PREFIX}/include;${_IMPORT_PREFIX}/include"
  INTERFACE_LINK_LIBRARIES "utf8cpp;polyclipping::polyclipping;Irrlicht;minizip::minizip;ZLIB::ZLIB;kubazip::kubazip;poly2tri::poly2tri"
)

but no find_dependency(utf8cpp CONFIG) at the top:

include(CMakeFindDependencyMacro)
find_dependency(ZLIB)
find_dependency(irrlicht CONFIG)
find_dependency(polyclipping CONFIG)
find_dependency(minizip CONFIG)
find_dependency(kubazip CONFIG)
find_dependency(poly2tri CONFIG)
# Generated by CMake

However, at a first inspection it seems that utf8cpp is header only and not used in the public headers, so it should simply not be a public link of the assimp::assimp target.

Expected behavior
All the imported targets linked by assimp target should be properly found in the CMake config file with a find_dependency call.

Failure logs
-(please attached failure logs)

Additional context
See gazebosim/gz-physics#87 (comment) .

[traversaro]

fyi @JackBoosY

[JackBoosY]

@traversaro Yep, I missed find_dependency. And the utf8cpp is a header only library.