Sidecar example code fails to download file

[BrianHicks]

Describe the bug

Since the curl command doesn't use --fail, a 404 fails to download the binary silently, resulting in a file which only contains the text "Not found". Pointing AVP_VERSION at an existing release fixes the example code.

This is probably a simple fix, but I wanted to raise it to you so you could decide whether or not --fail makes sense to include.

To Reproduce
Steps to reproduce the behavior:

1. Install the example sidecar code from /manifests/cmp-sidecar/argocd-repo-server.yaml in this repo
2. Sync an app

Expected behavior
argocd-vault-plugin runs successfully.