venv in install folder

[pardallio]

When building with ecbuild and exporting library headers, the install step takes especially long because it also installs the full fckit venv

fckit/cmake/fckit_install_venv.cmake

Lines 65 to 67 in 42aef06

	if( ECBUILD_INSTALL_LIBRARY_HEADERS )
	install( DIRECTORY ${VENV_PATH} DESTINATION . PATTERN "bin/*" PERMISSIONS ${install_permissions} )
	endif()

It would be better to have a specific option for installing the venv by adding it on CMakelists.txt

ecbuild_add_option( FEATURE FCKIT_INSTALL_VENV
                    DEFAULT OFF
                    DESCRIPTION "Install Python virtual environment with fypp and a yaml parser"
                    CONDITION Python3_VERSION VERSION_GREATER_EQUAL 3.8 )

and change those lines in https://github.com/ecmwf/fckit/blob/42aef06cf245f9c75c85f85dcf3bcdb7c62d0ad3/cmake/fckit_install_venv.cmake to

if( HAVE_FCKIT_INSTALL_VENV )
       install( DIRECTORY ${VENV_PATH} DESTINATION . PATTERN "bin/*" PERMISSIONS ${install_permissions} )
    endif()

[wdeconinck]

Hi @pardallio this should now be merged in develop.