Workflow Ubuntu 20.04 x64 with CUDA support (5.x)

Author: asenyaev

.github/workflows/PR-5.x.yaml

@@ -12,6 +12,10 @@ jobs:
   Ubuntu2004-x64:
     uses: opencv/ci-gha-workflow/.github/workflows/OCV-Contrib-PR-5.x-U20.yaml@main
 
+  Ubuntu2004-x64-CUDA:
+    if: "${{ contains(github.event.pull_request.labels.*.name, 'category: cuda') }}"
+    uses: opencv/ci-gha-workflow/.github/workflows/OCV-Contrib-PR-5.x-U20-Cuda.yaml@main
+
   Windows10-x64:
     uses: opencv/ci-gha-workflow/.github/workflows/OCV-Contrib-PR-5.x-W10.yaml@main