fix(deps): upgrade git2 to 0.21.0

third_party/gpui_support/gpui_util/Cargo.toml

@@ -66,7 +66,7 @@ version = "0.3"
 version = "1.13"
 
 [dependencies.git2]
-version = "0.20.1"
+version = "0.21.0"
 optional = true
 default-features = false
 
@@ -142,7 +142,7 @@ version = "2.5"
 version = "6.0.0"
 
 [dev-dependencies.git2]
-version = "0.20.1"
+version = "0.21.0"
 default-features = false
 
 [dev-dependencies.indoc]