refactor: remove cli::resources::Resource

[bartlomieju]

Blocked on #3271 (because based on that work)

Goal of this PR is to completely remove cli::resources::Resource and remove CoreResource type alias. Done

[bartlomieju]

CC @ry

[bartlomieju]

It'd be nice to remove this hack:

deno/cli/resources.rs

Lines 313 to 349 in 415d4c2

	// TODO: revamp this after the following lands:
	// https://github.com/tokio-rs/tokio/pull/785
	pub fn get_file(rid: ResourceId) -> Result<std::fs::File, ErrBox> {
	let mut table = lock_resource_table();
	// We take ownership of File here.
	// It is put back below while still holding the lock.
	let (_name, repr) = table.map.remove(&rid).ok_or_else(bad_resource)?;
	let repr = repr
	.downcast::<CliResource>()
	.or_else(|_| Err(bad_resource()))?;
	match *repr {
	CliResource::FsFile(r) => {
	// Trait Clone not implemented on tokio::fs::File,
	// so convert to std File first.
	let std_file = r.into_std();
	// Create a copy and immediately put back.
	// We don't want to block other resource ops.
	// try_clone() would yield a copy containing the same
	// underlying fd, so operations on the copy would also
	// affect the one in resource table, and we don't need
	// to write back.
	let maybe_std_file_copy = std_file.try_clone();
	// Insert the entry back with the same rid.
	table.map.insert(
	rid,
	(
	"fsFile".to_string(),
	Box::new(CliResource::FsFile(tokio_fs::File::from_std(std_file))),
	),
	);
	maybe_std_file_copy.map_err(ErrBox::from)
	}
	_ => Err(bad_resource()),
	}
	}

It'd be possible if we changed Deno.run to be asynchronous function instead of sync one. WDYT?

[ry]

LGTM - good clean up