Link plugin dependencies to libraries, not test executables.

The test executables shouldn't need it at all.

src/Plugins/MagnumFontConverter/CMakeLists.txt

@@ -47,6 +47,7 @@ if(BUILD_GL_TESTS)
     add_library(MagnumFontConverterTestLib STATIC $<TARGET_OBJECTS:MagnumFontConverterObjects>)
     target_link_libraries(MagnumFontConverterTestLib
         ${MAGNUM_LIBRARIES}
-        ${MAGNUM_TEXT_LIBRARIES})
+        ${MAGNUM_TEXT_LIBRARIES}
+        TgaImageConverterTestLib)
     add_subdirectory(Test)
 endif()

src/Plugins/MagnumFontConverter/Test/CMakeLists.txt

@@ -32,6 +32,5 @@ include_directories(${CMAKE_CURRENT_BINARY_DIR}/../../FreeTypeFont/Test/
 corrade_add_test(MagnumFontConverterTest MagnumFontConverterTest.cpp LIBRARIES
     MagnumFontConverterTestLib
     FreeTypeFontTestLib
-    TgaImageConverterTestLib
     TgaImporterTestLib
     ${GL_TEST_LIBRARIES})