Add test workflow.

.github/workflows/test.yaml

@@ -0,0 +1,23 @@
+name: test
+
+on:
+  workflow_dispatch:
+    inputs:
+      branch:
+        required: true
+        type: string
+      date:
+        required: true
+        type: string
+      sha:
+        required: true
+        type: string
+
+jobs:
+  test-conda-nightly-env:
+    secrets: inherit
+    # We use a build workflow so that we get CPU jobs and high matrix coverage
+    uses: rapidsai/shared-workflows/.github/workflows/[email protected]
+    with:
+      build_type: pull-request
+      script: "ci/test_conda_nightly_env.sh"