Add mlir override to concurrency group (#429)

Solves issue with multiple "On PR" CI runs targeting "main" but using
different "mlir_override" inputs would collide and cancel earlier job.
Adding mlir override input to concurrency group name to resolve this.

Author: nsumrakTT

.github/workflows/on-pr.yml

@@ -11,7 +11,7 @@ on:
     branches: [ "main" ]
 
 concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
+  group: ${{ github.workflow }}-${{ github.ref }}-${{ inputs.mlir_override }}
   cancel-in-progress: true
 
 jobs: