Update Rust crate git2 to v0.15.0 (#5016)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Cargo.lock

@@ -17,7 +17,7 @@ testing = ["serde_json"]
 anyhow = "=1.0.58"
 base64 = "=0.13.0"
 dotenv = "=0.15.0"
-git2 = "=0.14.4"
+git2 = "=0.15.0"
 serde = { version = "=1.0.140", features = ["derive"] }
 tempfile = "=3.3.0"
 url = "=2.2.2"