Fix version numbers in readme for the linter

Co-authored-by: Paula <[email protected]>

README.md

@@ -12,7 +12,7 @@ This will login docker to ECR prior to running your script.
 steps:
   - command: ./run_build.sh
     plugins:
-      - ecr#v2.1.1:
+      - ecr#v2.3.0:
           login: true
 ```
 
@@ -22,7 +22,7 @@ If you want to log in to ECR on [another account](https://docs.aws.amazon.com/Am
 steps:
   - command: ./run_build.sh
     plugins:
-      - ecr#v2.1.1:
+      - ecr#v2.3.0:
           login: true
           account_ids: "0015615400570"
           region: "ap-southeast-2"
@@ -34,7 +34,7 @@ If you need to assume a role to perform that login:
 steps:
   - command: ./run_build.sh
     plugins:
-      - ecr#v2.1.1:
+      - ecr#v2.3.0:
           login: true
           account_ids: "0015615400570"
           region: "ap-southeast-2"