Upgrade devcontainer go version to 1.24.6 (#35298)

Addresses go version mismatch when using the devcontainer as a result of
[this
commit](793815adf7)
(bumps Go version from 1.24.5 to 1.24.6)

The current official devcontainer Go image used in this repository
(`1.24-bookworm`) uses 1.24.5 and sets GOTOOLCHAIN to local. This PR
overrides it to auto so that build commands automatically update to the
correct version.

---------

Signed-off-by: Jackson Stewart <jaxtew@pm.me>
Co-authored-by: techknowlogick <techknowlogick@gitea.com>

.devcontainer/devcontainer.json

@@ -1,6 +1,10 @@
 {
   "name": "Gitea DevContainer",
   "image": "mcr.microsoft.com/devcontainers/go:1.24-bookworm",
+  "containerEnv": {
+    // override "local" from packaged version
+    "GOTOOLCHAIN": "auto"
+  },
   "features": {
     // installs nodejs into container
     "ghcr.io/devcontainers/features/node:1": {