automated: Update flake.lock

- The following Nix Flake inputs were updated:

```
• Updated input 'nixpkgs':
    'path:/nix/store/jk6xpbfh10gz6q5cqw8b2f7xk0pl7hkv-source?lastModified=1741010256&narHash=sha256-WZNlK/KX7Sni0RyqLSqLPbK8k08Kq7H7RijPJbq9KHM%3D&rev=ba487dbc9d04e0634c64e3b1f0d25839a0a68246' (2025-03-03)
  → 'github:NixOS/nixpkgs/6c5963357f3c1c840201eda129a99d455074db04?narHash=sha256-yQugdVfi316qUfqzN8JMaA2vixl%2B45GxNm4oUfXlbgw%3D' (2025-03-27)
```

Auto-generated by [update.yml][1] with the help of
[create-pull-request][2].

[1]: https://forgejo.stefka.eu/jiriks74/nix.nvim/src/branch/main/.github/workflows/update.yml
[2]: https://forgejo.stefka.eu/jiriks74/create-pull-request

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1743689281,
-        "narHash": "sha256-y7Hg5lwWhEOgflEHRfzSH96BOt26LaYfrYWzZ+VoVdg=",
+        "lastModified": 1743076231,
+        "narHash": "sha256-yQugdVfi316qUfqzN8JMaA2vixl+45GxNm4oUfXlbgw=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "2bfc080955153be0be56724be6fa5477b4eefabb",
+        "rev": "6c5963357f3c1c840201eda129a99d455074db04",
         "type": "github"
       },
       "original": {