Remove retry logic (#389)

The retries make debugging strictly more complex, and it's not clear
that retrying provides actual value. If we need retries in the future,
we should push them down into the per-API level.

action.yml

@@ -132,24 +132,28 @@ inputs:
     default: ''
     required: false
 
-  # retries
+  # retries - TODO - remove in v3.0
   retries:
     description: |-
       Number of times to retry a failed authentication attempt. This is useful
       for automated pipelines that may execute before IAM permissions are fully
       propogated.
-    default: '3'
+    deprecationMessage: |-
+      This field is no longer used and will be removed in a future release.
     required: false
   backoff:
     description: |-
       Delay time before trying another authentication attempt. This is
       implemented using a fibonacci backoff method (e.g. 1-1-2-3-5). The default
       value is 250 milliseconds.
-    default: '250'
+    deprecationMessage: |-
+      This field is no longer used and will be removed in a future release.
     required: false
   backoff_limit:
     description: |-
       Limits the retry backoff to the specified value.
+    deprecationMessage: |-
+      This field is no longer used and will be removed in a future release.
     required: false
 
   # id token params