Module-Metadata: Fix UTF-8 BOM detection for non-ASCII

[khwilliamson]

No description provided.

[karenetheridge]

Is there any way to test this, so someone doesn't come along later and go "well tests pass without this, so I guess it's not necessary"?

[Leont]

Essentially this is a constant, and hence should probably be computed in a BEGIN block?

[khwilliamson]

Without this patch, it fails on z/OS EBCDIC with:

#   Failed test 'version for ASCII package'
#   at t/encoding.t line 27.
#          got: undef
#     expected: '1'

#   Failed test 'version for Unicode package'
#   at t/encoding.t line 28.
#          got: undef
#     expected: '2'
# Looks like you failed 2 tests of 12.
../cpan/Module-Metadata/t/encoding.t ................................. 
Dubious, test returned 2 (wstat 512, 0x200)
Failed 2/12 subtests

So, I guess I'm claiming there already is a test.

[khwilliamson]

BEGIN block comment is now addressed.