Run Compatibility GPU CI jobs only on upstream

Run Compatibility GPU CI jobs only on upstream,
since forks do not have the required HW.

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>

Author: ldorau

.github/workflows/reusable_compatibility.yml

@@ -186,6 +186,8 @@ jobs:
 
   gpu:
     name: GPU Ubuntu
+    # run only on upstream; forks will not have the HW
+    if: github.repository == 'oneapi-src/unified-memory-framework'
     strategy:
       matrix:
         provider: ['LEVEL_ZERO', 'CUDA']