The current Go version (1.13) is no longer supported

Upgrade the Go version of the operator to the most recent productisable version

Fix CVE:

• https://issues.redhat.com/browse/THREESCALE-8550
• https://issues.redhat.com/browse/THREESCALE-8551
• https://issues.redhat.com/browse/THREESCALE-8563
• https://issues.redhat.com/browse/THREESCALE-8564
• https://issues.redhat.com/browse/THREESCALE-8565
• https://issues.redhat.com/browse/THREESCALE-8566
• https://issues.redhat.com/browse/THREESCALE-8567
• https://issues.redhat.com/browse/THREESCALE-8568
• https://issues.redhat.com/browse/THREESCALE-8569
   

dev notes:

Targeting the following new deps

• Latest productised go version is 1.17, so let go be 1.17
• sigs.k8s.io/controller-runtime v0.11.2
• k8s.io/api v0.23.5
• k8s.io/apimachinery v0.23.5
• k8s.io/client-go v0.23.5 (this dependency is set in the "replace")

All the current "replaces" in the go.mod should be removed, except for the client-go

Grafana dep needs to be bumped to a new *major* version, from 3.6.0 -> 4.x, because grafana 3.X does not compile with controller-runtime v0.11.2

github.com/3scale/3scale-operator imports
	github.com/integr8ly/grafana-operator/v3/pkg/apis/integreatly/v1alpha1 imports
	sigs.k8s.io/controller-runtime/pkg/runtime/scheme: module sigs.k8s.io/controller-runtime@latest found (v0.13.0), but does not contain package sigs.k8s.io/controller-runtime/pkg/runtime/scheme

This major upgrade (3.x -> 4.x) breaks the backward compat of the grafana dashboard APIs. The 3scale operator would be reconciling effectively new grafana object. The grafana
dashboard upgrade doc should be done if the grafana operator upgrade (which is required as well) does not do by itself. This issue needs to be analyzed and tested.

The work done so far can be found in the "upgrade-deps" branch https://github.com/3scale/3scale-operator/compare/upgrade-deps?expand=1 It is not finished, just version bumping of the go.mod file. The new grafana dashboard API, requires changes in the code. The new controller runtime also requires changes in the code (the context is given as the Reconcile method argument)