Update bitstream-io requirement from 1.0 to 2.0

Updates the requirements on [bitstream-io](https://github.com/tuffy/bitstream-io) to permit the latest version.
- [Commits](tuffy/bitstream-io@v1.0.0...v2.0.0)

---
updated-dependencies:
- dependency-name: bitstream-io
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

tools/Cargo.toml

@@ -6,6 +6,6 @@ edition = "2018"
 
 [dependencies]
 dav1d = { path = "..", version = "0.10" }
-bitstream-io = "1.0"
+bitstream-io = "2.0"
 log = "0.4"
 structopt = "0.3"