[perl #119121] [BUG] Heredoc indented with a tab doesn't de-indent properly in Rakudo

[Christian Bartolomaeus via RT]

I'm closing this ticket since this works now and there are tests in 
S02-literals/heredocs.t (cmp. commit 
https://github.com/perl6/roast/commit/978e4a8ac166821ab18a8c02c906063b6e489dd6)

$ perl6 -e 'say (EVAL "q:to/E/;\n\tfoo\n\tbar\n\tE") eq "foo\nbar\n"'
True

$ perl6 -e 'say (EVAL "q:to/E/;\n\tfoo\n\tbar\nE") eq "\tfoo\n\tbar\n"'
True