Swap out deprecated runner (#2345)

Summary:
Github is deprecating the `N-core-ubuntu` runner label, replacing it with `N-core`.  We need to migrate PyTorch runners accordingly

This only affects how github queues jobs, not where those jobs actually run

More details in pytorch/pytorch#125721

Pull Request resolved: #2345

Reviewed By: saitcakmak

Differential Revision: D57384735

Pulled By: ZainRizvi

fbshipit-source-id: f0128dab657c821cd107a073daf56c5567c9fc00

Author: ZainRizvi

.github/workflows/deploy_on_release.yml

@@ -46,7 +46,7 @@ jobs:
 
   package-deploy-conda:
     name: Package conda and deploy to anaconda.org
-    runs-on: 8-core-ubuntu
+    runs-on: 8-core
     needs: tests-and-coverage-pip
     steps:
     - uses: actions/checkout@v4

.github/workflows/nightly.yml

@@ -62,7 +62,7 @@ jobs:
 
   package-conda:
     name: Test conda build
-    runs-on: 8-core-ubuntu
+    runs-on: 8-core
     steps:
     - uses: actions/checkout@v4
     - uses: conda-incubator/setup-miniconda@v3