Fix TAG_THROW through require [Bug #18562]

    Previously this was being incorrectly swapped with TAG_RAISE in the next
    line. This would end up checking the T_IMEMO throw_data to the exception
    handling (which calls Module#===). This happened to not break existing
    tests because Module#=== returned false when klass is NULL.

    This commit handles throw from require correctly by jumping to the tag
    retaining the TAG_THROW state.
    ---
     load.c                      |  2 +-
     test/ruby/test_exception.rb | 21 +++++++++++++++++++++
     2 files changed, 22 insertions(+), 1 deletion(-)