Merge pull request #138 from chenrui333/update-git2

chore(deps): update git2 to use libgit2 1.9

Author: tummychow

Cargo.lock

@@ -22,7 +22,7 @@ name = "git-absorb"
 path = "src/main.rs"
 
 [dependencies.git2]
-version = "0.19"
+version = "0.20"
 default-features = false
 
 [dependencies]