nix: flake update

bacon 3.6.0 -> 3.8.0, shows output with nextest 0.9.86
https://github.com/Canop/bacon/issues/280

Add python3 to the devshell to be able to run tools installed with uv

flake.lock

@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1735648875,
-        "narHash": "sha256-fQ4k/hyQiH9RRPznztsA9kbcDajvwV1sRm01el6Sr3c=",
+        "lastModified": 1737557748,
+        "narHash": "sha256-BaMuhctP1x00+8cBE2cJveJQb70/tWHI50MHj/ZrtOY=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "47e29c20abef74c45322eca25ca1550cdf5c3b50",
+        "rev": "606996d74f6e2a12635d41c1bf58bfc7ea3bb5ec",
         "type": "github"
       },
       "original": {
@@ -48,11 +48,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1735784864,
-        "narHash": "sha256-tIl5p3ueaPw7T5T1UXkLc8ISMk6Y8CI/D/rd0msf73I=",
+        "lastModified": 1737685583,
+        "narHash": "sha256-p+NVABRpGi+pT+xxf9HcLcFVxG6L+vEEy+NwzB9T0f8=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "04d5f1836721461b256ec452883362c5edc5288e",
+        "rev": "eb64cbcc8eee0fa87ebded92805280d2ec97415a",
         "type": "github"
       },
       "original": {

flake.nix

@@ -164,6 +164,8 @@
 
           # For building the documentation website
           uv
+          # nixos does not work with uv-installed python
+          python3
         ];
 
         # on macOS and Linux, use faster parallel linkers that are much more