fix(ci): ensure 'auto' toolchain applies to generate (#3436)

Author: dnwe

script/generate.sh

@@ -6,6 +6,10 @@ set -e
 
 CDPATH="" cd -- "$(dirname -- "$0")/.."
 
+# force 1.22.0 default and "auto" toolchain (i.e., use the toolchain directive)
+# when running generate and mod tidy
+export GOTOOLCHAIN="go1.22.0+auto"
+
 if [ "$1" = "--check" ]; then
   GENTEMP="$(mktemp -d)"
   git worktree add -q --detach "$GENTEMP"
@@ -43,6 +47,6 @@ for dir in $MOD_DIRS; do
   (
     cd "$dir"
     go generate ./...
-    GOTOOLCHAIN="go1.22+auto" go mod tidy
+    go mod tidy
   )
 done