fix(cabal.project parser): parse the packages ending with eof

[shivaraj-bh]

To reproduce:

git clone git@github.com:srid/haskell-flake.git
curl https://github.com/raw/shivaraj-bh/haskell-flake/c80a145a228631161a16fcbb5edbc6a5171803ad/test/with-subdir/cabal.project > test/with-subdir/cabal.project
, test

[srid]

Could you add a unit test for this case (ending with eof) here?

haskell-flake/nix/haskell-parsers/parser_tests.nix

Lines 5 to 20 in c301f31

	cabalProjectTests =
	let
	eval = s:
	let res = parser.parseCabalProjectPackages s; in
	if res.type == "success" then res.value else res;
	in
	{
	testSimple = {
	expr = eval ''
	packages:
	foo
	bar
	'';
	expected = [ "foo" "bar" ];
	};
	};

[shivaraj-bh]

@srid unit test added