t/pmc/iterator.t: split test

[jkeenan]

perlcritic.t flagged a TODO comment in this file. So it must be replaced with a Trac ticket citation. Here is the comment in its original form:

# XXX Split this test into aggregate specific one.

Now, it's not clear to me whether this comment refers to the test immediately following the comment, ...

pasm_output_is( <<'CODE', <<'OUTPUT', "new iter" );
    new P2, ['ResizablePMCArray']
    iter P1, P2
    print "ok 1\n"
    end
CODE
ok 1
OUTPUT

... or whether it refers to this file as a whole. Since SVN praises bacek for this comment written in r40191, I am assigning ticket.

[bacek]

Adding "newbie" keyword since it's actually newbie task to just move bits around.

[coke]

kthakore++ notes that this test is gone.

Comment isn't in t/pmc anywhere else, either.