[CI] Enable BMG testing on Windows

Author: lukaszstolarczuk

.github/workflows/nightly.yml

@@ -466,7 +466,6 @@ jobs:
     with:
       provider: "LEVEL_ZERO"
       runner: "L0-BMG"
-      os: "['Ubuntu']"
   CUDA:
     uses: ./.github/workflows/reusable_gpu.yml
     with:

.github/workflows/pr_push.yml

@@ -47,7 +47,6 @@ jobs:
       provider: "LEVEL_ZERO"
       runner: "L0-BMG"
       shared_lib: "['ON']"
-      os: "['Ubuntu']"
   CUDA:
     needs: [Build]
     uses: ./.github/workflows/reusable_gpu.yml