Merge from rustc

Author: RalfJung

.github/renovate.json5

@@ -0,0 +1,14 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  // Let Renovatebot keep an opened issue that tracks our dependencies
+  "dependencyDashboard": true,
+  // Disable "normal" package updates
+  "enabledManagers": [],
+  // Update lockfiles once per week
+  "lockFileMaintenance": {
+    "enabled": true,
+    "schedule": [
+      "before 5am on Tuesday"
+    ]
+  }
+}

.gitignore

@@ -88,12 +88,12 @@ package.json
 tests/rustdoc-gui/src/**.lock
 
 ## direnv
-.envrc
-.direnv/
+/.envrc
+/.direnv/
 
 ## nix
-flake.nix
+/flake.nix
 flake.lock
-default.nix
+/default.nix
 
 # Before adding new lines, see the comment at the top.