infra: remove generate contrib workflows from core

Signed-off-by: emdneto <[email protected]>

Author: emdneto

.github/workflows/contrib.yml

@@ -0,0 +1,14 @@
+name: Core Contrib Test
+
+on:
+  push:
+    branches-ignore:
+    - 'release/*'
+  pull_request:
+
+jobs:
+  contrib_0:
+    uses: open-telemetry/opentelemetry-python-contrib/.github/workflows/core_contrib_test_0.yml@main
+    with:
+      CORE_REPO_SHA: ${{ github.sha }}
+      CONTRIB_REPO_SHA: main