Update git2-ext dependency (#220)

The latest git2-ext release is compatible with an up-to-date git2
dependency

Author: spacedentist

Cargo.lock

@@ -16,7 +16,7 @@ dialoguer = "^0.11.0"
 futures = "^0.3.31"
 futures-lite = "^2.6.0"
 git2 = { version = "^0.20.1", default-features = false }
-git2-ext ={ git="https://github.com/mhammerly/git2-ext.git", rev = "115a912b7b89d91c03d1e52e0d39b60adb04dde6" }
+git2-ext = "^0.6.3"
 graphql_client = "^0.14.0"
 indoc = "^2.0.6"
 lazy-regex = "^3.4.1"