[OpCompat] add fetch and update mish in op_compat.yaml (#55422)

* [OpCompat] add fetch and update mish in op_compat.yaml

* add missing outputs

* fix codestyle

paddle/phi/api/yaml/op_compat.yaml

@@ -1864,7 +1864,9 @@
 - op : mish
   backward : mish_grad
   inputs:
-    lambda:  threshold
+    {x : X, lambda : threshold}
+  outputs:
+    out: Out
   extra :
     attrs : [bool use_mkldnn = false]
 
@@ -2985,6 +2987,10 @@
     yolo_loss : GetYoloLossExpectedKernelType
     yolo_loss_grad : GetYoloLossExpectedKernelType
 
+- op: fetch
+  inputs: {x: X}
+  outputs: {out: Out}
+
 - op: full_batch_size_like (fill_constant_batch_size_like)
 
 - op: lu