bugfix: Docs for installation overlook the access-key

## Expected Behaviour

Quick issue, followed by bugfix:
The README overlooks the installation step and if you use `ark install inlets-operator` you might not have the secret installed properly (the operator refers to the secret by a different name)

## Current Behaviour
the operator container will fail to load....

## Possible Solution
updated the README with tips.

## Steps to Reproduce (for bugs)

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## Context

## Your Environment

* inlets-operator version, find via `kubectl get deploy inlets-operator -o wide`

* Kubernetes distribution i.e. minikube v0.29.0., KinD v0.5.1, Docker Desktop:

* Kubernetes version `kubectl version`:

* Operating System and version (e.g. Linux, Windows, MacOS):

* Cloud provisioner: