Update tokio-util to 0.7.0 (tower-rs#221)

* tokio-util: 0.6.8 -> 0.7.0

This mirrors tower-rs/tower#638.

* Bump tokio requirement to 1.6

According to tower-rs/tower#638, this is now required
by tokio-util, but declared incorrectly.

Author: nightkr

deny.toml

@@ -37,10 +37,6 @@ license-files = [
 multiple-versions = "deny"
 highlight = "all"
 skip-tree = [{ name = "tower", version = ">=0.3, <=0.4" }]
-skip = [
-    # pulled in by hyper, http, and serde_urlencoded
-    { name = "itoa", version = "=0.4.8" },
-]
 
 [sources]
 unknown-registry = "warn"

tower-http/Cargo.toml

@@ -31,8 +31,8 @@ iri-string = { version = "0.4", optional = true }
 mime = { version = "0.3", optional = true, default_features = false }
 mime_guess = { version = "2", optional = true, default_features = false }
 percent-encoding = { version = "2.1.0", optional = true }
-tokio = { version = "1", optional = true, default_features = false }
-tokio-util = { version = "0.6.8", optional = true, default_features = false, features = ["io"] }
+tokio = { version = "1.6", optional = true, default_features = false }
+tokio-util = { version = "0.7", optional = true, default_features = false, features = ["io"] }
 tower = { version = "0.4.1", optional = true }
 tracing = { version = "0.1", default_features = false, optional = true }
 httpdate = { version = "1.0", optional = true }