refresh token tests check std.err for warnings if `CF_CLI_EXPERIMENTAL` is true
refresh token tests check std.err for warnings if `CF_CLI_EXPERIMENTAL`
is true

[#126256695]

Signed-off-by: Alex Melnik <133b34882c9a7536fb0c644d95ec8ca567374456@hpe.com>

fujitsu-cf/cli,simonleung8/cli,simonleung8/cli,fujitsu-cf/cli,fujitsu-cf/cli,simonleung8/cli