Update Ruby versions (#153)

Automatically created pull-request to update Ruby and Rubygems versions.

This is the result of running:

```
nix run .#update
```

See the workflow here:
https://github.com/bobvanderlinden/nixpkgs-ruby/blob/master/.github/workflows/update.yml

ruby/versions.json

@@ -871,13 +871,17 @@
     "3.2.6": {
       "url": "https://cache.ruby-lang.org/pub/ruby/3.2/ruby-3.2.6.tar.gz",
       "sha256": "d9cb65ecdf3f18669639f2638b63379ed6fbb17d93ae4e726d4eb2bf68a48370"
+    },
+    "3.3.6": {
+      "url": "https://cache.ruby-lang.org/pub/ruby/3.3/ruby-3.3.6.tar.gz",
+      "sha256": "8dc48fffaf270f86f1019053f28e51e4da4cce32a36760a0603a9aee67d7fd8d"
     }
   },
   "aliases": {
     "2": "2.7.8",
-    "3": "3.3.5",
-    "latest": "3.3.5",
-    "3.3": "3.3.5",
+    "3": "3.3.6",
+    "latest": "3.3.6",
+    "3.3": "3.3.6",
     "3.2": "3.2.6",
     "3.1": "3.1.6",
     "3.0": "3.0.7",
@@ -889,8 +893,8 @@
     "2.2": "2.2.10",
     "2.1": "2.1.10",
     "2.*": "2.7.8",
-    "3.*": "3.3.5",
-    "3.3.*": "3.3.5",
+    "3.*": "3.3.6",
+    "3.3.*": "3.3.6",
     "3.2.*": "3.2.6",
     "3.1.*": "3.1.6",
     "3.0.*": "3.0.7",