Gate all PR builds behind linux-x86_64-cmake in GitHub Actions (facebookresearch#3476)

Summary:
Pull Request resolved: facebookresearch#3476

The long tail will still be the RAFT build but we can save on cost if the build has errors by incurring ~10m penalty added by waiting for the basic cmake build to complete. Both GPU and RAFT builds will start together so this will take less time overall to complete.

Reviewed By: algoriddle

Differential Revision: D57707298

fbshipit-source-id: 3589842e9bda9ebca9b25e089e6177fe96b6a0f5

Author: ramilbakhshyiev

.github/workflows/build.yml

@@ -46,6 +46,7 @@ jobs:
       - uses: ./.github/actions/build_cmake
   linux-x86_64-AVX2-cmake:
     name: Linux x86_64 AVX2 (cmake)
+    needs: linux-x86_64-cmake
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -56,6 +57,7 @@ jobs:
   linux-x86_64-AVX512-cmake:
     name: Linux x86_64 AVX512 (cmake)
     if: false # TODO: enable when GitHub Actions adds AVX-512 hosts
+    needs: linux-x86_64-cmake
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -65,7 +67,7 @@ jobs:
           opt_level: avx512
   linux-x86_64-GPU-cmake:
     name: Linux x86_64 GPU (cmake)
-    needs: linux-x86_64-AVX2-cmake
+    needs: linux-x86_64-cmake
     runs-on: 4-core-ubuntu-gpu-t4
     steps:
       - name: Checkout
@@ -75,6 +77,7 @@ jobs:
           gpu: ON
   linux-x86_64-GPU-w-RAFT-cmake:
     name: Linux x86_64 GPU w/ RAFT (cmake)
+    needs: linux-x86_64-cmake
     runs-on: 4-core-ubuntu-gpu-t4
     steps:
       - name: Checkout
@@ -85,6 +88,7 @@ jobs:
           raft: ON
   linux-x86_64-conda:
     name: Linux x86_64 (conda)
+    needs: linux-x86_64-cmake
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -95,6 +99,7 @@ jobs:
       - uses: ./.github/actions/build_conda
   windows-x86_64-conda:
     name: Windows x86_64 (conda)
+    needs: linux-x86_64-cmake
     runs-on: windows-2019
     steps:
       - name: Checkout
@@ -105,6 +110,7 @@ jobs:
       - uses: ./.github/actions/build_conda
   linux-arm64-conda:
     name: Linux arm64 (conda)
+    needs: linux-x86_64-cmake
     runs-on: 2-core-ubuntu-arm
     steps:
       - name: Checkout