Revert "ci: migrate sdk-regenerate pipeline from autorest.go"

This reverts commit 6300d67.

Author: tadelesh

eng/pipelines/sdk-regenerate.yml

@@ -1,6 +1,3 @@
 variables:
   # Disable CodeQL by default to prevent build timeouts
   Codeql.SkipTaskAutoInjection: true
-  # Node.js version used by pipelines that install Node via NodeTool (e.g. the
-  # typespec-go SDK regeneration pipeline).
-  NodeVersion: "24.x"