Update linux-dnnl.yml: rename the pipeline (microsoft#24240)

Update linux-dnnl.yml: rename the pipeline to Linux DNNL CI

Author: Changming Sun

.github/workflows/linux-dnnl.yml

@@ -4,7 +4,7 @@
 # This file is very similar to linux_ci.yml, but much simpler
 
 
-name: Linux CI
+name: Linux DNNL CI
 
 on:
   push: