Update outdated dependencies

Signed-off-by: koushiro <[email protected]>

README.md

@@ -2,6 +2,7 @@
 [![Windows Build Status](https://ci.appveyor.com/api/projects/status/24rpba3x2vqe8lje/branch/master?svg=true)](https://ci.appveyor.com/project/danburkert/prost/branch/master)
 [![Documentation](https://docs.rs/prost/badge.svg)](https://docs.rs/prost/)
 [![Crate](https://img.shields.io/crates/v/prost.svg)](https://crates.io/crates/prost)
+[![Dependency Status](https://deps.rs/repo/github/danburkert/prost/status.svg)](https://deps.rs/repo/github/danburkert/prost)
 
 # *PROST!*
 

conformance/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 [dependencies]
 bytes = "0.5"
 env_logger = { version = "0.7", default-features = false }
-log = "0.3"
+log = "0.4"
 prost = { path = ".." }
 protobuf = { path = "../protobuf" }
 tests = { path = "../tests" }

prost-build/Cargo.toml

@@ -14,14 +14,14 @@ bytes = "0.5"
 heck = "0.3"
 itertools = "0.8"
 log = "0.4"
-multimap = { version = "0.4", default-features = false }
-petgraph = { version = "0.4", default-features = false }
+multimap = { version = "0.8", default-features = false }
+petgraph = { version = "0.5", default-features = false }
 prost = { version = "0.6.0", path = ".." }
 prost-types = { version = "0.6.0", path = "../prost-types" }
 tempfile = "3"
 
 [build-dependencies]
-which = "2"
+which = { version = "3", default-features = false }
 
 [dev-dependencies]
 env_logger = { version = "0.7", default-features = false }