Auto merge of #8998 - ehuss:update-git2, r=alexcrichton

Update git2

Hopefully this will finally fix #8517 (and hopefully won't cause much breakage).

Major changes:
- Requires libgit2 1.1: rust-lang/git2-rs#632
- Update libgit2: rust-lang/git2-rs#642  (changes: libgit2/libgit2@7f4fa17...530d37b)

Author: bors

Cargo.toml

@@ -32,8 +32,8 @@ pretty_env_logger = { version = "0.4", optional = true }
 anyhow = "1.0"
 filetime = "0.2.9"
 flate2 = { version = "1.0.3", default-features = false, features = ["zlib"] }
-git2 = "0.13.12"
-git2-curl = "0.14.0"
+git2 = "0.13.13"
+git2-curl = "0.14.1"
 glob = "0.3.0"
 hex = "0.4"
 home = "0.5"
@@ -44,7 +44,7 @@ jobserver = "0.1.21"
 lazycell = "1.2.0"
 libc = "0.2"
 log = "0.4.6"
-libgit2-sys = "0.12.14"
+libgit2-sys = "0.12.15"
 memchr = "2.1.3"
 num_cpus = "1.0"
 opener = "0.4"