.github: Increase test shards for linux GPU (#60914)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/60914

Linux GPU tests are taking almost 4 hours to execute through, let's up
the test shards for these jobs so they finish in a more timely fashion

Signed-off-by: Eli Uriegas <eliuriegas@fb.com>

Test Plan: Imported from OSS

Reviewed By: samestep

Differential Revision: D29461968

Pulled By: seemethere

fbshipit-source-id: a1eab08f9cd3abd8ceca48871fe702d0bccd8a3f
diff --git a/.github/scripts/generate_ci_workflows.py b/.github/scripts/generate_ci_workflows.py
index 2bd1a7f..a076cde 100755
--- a/.github/scripts/generate_ci_workflows.py
+++ b/.github/scripts/generate_ci_workflows.py
@@ -141,16 +141,19 @@
         build_environment="pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7",
         docker_image_base=f"{DOCKER_REGISTRY}/pytorch/pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7",
         test_runner_type=LINUX_CUDA_TEST_RUNNER,
+        num_test_shards=2,
     ),
     PyTorchLinuxWorkflow(
         build_environment="pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7",
         docker_image_base=f"{DOCKER_REGISTRY}/pytorch/pytorch-linux-xenial-cuda10.2-cudnn7-py3-gcc7",
         test_runner_type=LINUX_CUDA_TEST_RUNNER,
+        num_test_shards=2,
     ),
     PyTorchLinuxWorkflow(
         build_environment="pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7",
         docker_image_base=f"{DOCKER_REGISTRY}/pytorch/pytorch-linux-xenial-cuda11.1-cudnn8-py3-gcc7",
         test_runner_type=LINUX_CUDA_TEST_RUNNER,
+        num_test_shards=2,
     ),
     # PyTorchLinuxWorkflow(
     #     build_environment="pytorch-libtorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7",
diff --git a/.github/workflows/pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7.yml b/.github/workflows/pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7.yml
index 80448b8..38d5c59 100644
--- a/.github/workflows/pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7.yml
+++ b/.github/workflows/pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7.yml
@@ -193,7 +193,7 @@
     if: ${{ github.repository_owner == 'pytorch' }}
     runs-on: ubuntu-18.04
     env:
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     container:
@@ -221,7 +221,7 @@
     env:
       DOCKER_IMAGE: ${{ needs.calculate-docker-image.outputs.docker_image }}
       JOB_BASE_NAME: pytorch-linux-bionic-cuda10.2-cudnn7-py3.9-gcc7-test
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
       TEST_CONFIG: ${{ matrix.test_config }}
     steps:
       - name: Log in to ECR
diff --git a/.github/workflows/pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7.yml b/.github/workflows/pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7.yml
index 4f4e8d3..38a48a1 100644
--- a/.github/workflows/pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7.yml
+++ b/.github/workflows/pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7.yml
@@ -193,7 +193,7 @@
     if: ${{ github.repository_owner == 'pytorch' }}
     runs-on: ubuntu-18.04
     env:
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     container:
@@ -221,7 +221,7 @@
     env:
       DOCKER_IMAGE: ${{ needs.calculate-docker-image.outputs.docker_image }}
       JOB_BASE_NAME: pytorch-linux-xenial-cuda10.2-cudnn7-py3.6-gcc7-test
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
       TEST_CONFIG: ${{ matrix.test_config }}
     steps:
       - name: Log in to ECR
diff --git a/.github/workflows/pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7.yml b/.github/workflows/pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7.yml
index bf4396b..dbf337d 100644
--- a/.github/workflows/pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7.yml
+++ b/.github/workflows/pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7.yml
@@ -193,7 +193,7 @@
     if: ${{ github.repository_owner == 'pytorch' }}
     runs-on: ubuntu-18.04
     env:
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     container:
@@ -221,7 +221,7 @@
     env:
       DOCKER_IMAGE: ${{ needs.calculate-docker-image.outputs.docker_image }}
       JOB_BASE_NAME: pytorch-linux-xenial-cuda11.1-cudnn8-py3.6-gcc7-test
-      NUM_TEST_SHARDS: 1
+      NUM_TEST_SHARDS: 2
       TEST_CONFIG: ${{ matrix.test_config }}
     steps:
       - name: Log in to ECR