Revert "[tools] Temporarily make Node.js bot experimental"

This reverts commit 5f9b9b99.

Reason for revert: not longer necessary.

Original change's description:
> [tools] Temporarily make Node.js bot experimental
> 
> R=​sergiyb@chromium.org,yangguo@chromium.org
> NOTRY=true
> 
> Bug: v8:8397
> Change-Id: I528642fe0cf023fab7d653e9370a0d5a39a6bbb4
> Reviewed-on: https://chromium-review.googlesource.com/c/1310198
> Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
> Commit-Queue: Maya Lekova <mslekova@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#57179}

TBR=yangguo@chromium.org,sergiyb@chromium.org,mslekova@chromium.org

Change-Id: Iaa14f5358f925313a450916c5caaa355b00e07be
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:8397
Reviewed-on: https://chromium-review.googlesource.com/c/1310873Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57185}

infra/config/cq.cfg

@@ -90,10 +90,7 @@ verifiers {
         name: "v8_mac64_rel_ng_triggered"
         triggered_by: "v8_mac64_rel_ng"
       }
-      builders {
-        name: "v8_node_linux64_rel"
-        experiment_percentage: 100
-      }
+      builders { name: "v8_node_linux64_rel" }
       builders {
         name: "v8_presubmit"
         disable_reuse: true