cargo: depend on at least hyper 0.11.9

This release fixes an issue that occurred frequently with Gitlab
communication.

See https://github.com/hyperium/hyper/issues/1396 for details.

Cargo.toml

@@ -13,7 +13,7 @@ keywords = ["gitlab", "api"]
 categories = ["web-programming", "api-bindings"]
 
 [dependencies]
-hyper = { version = "~0.11", default-features = false }
+hyper = { version = "~0.11.9", default-features = false }
 itertools = "~0.7"
 log = "~0.3"
 reqwest = "~0.8"