refactor: Use separate types for provider cluster configs (#537)

**What problem does this PR solve?**:
This commit also switches to using controller-gen generated CRDs
for the OpenAPI schema for the variable definitions.

A lot of this commit is refactoring tests.

The mechanism for defining the variable schema changes with this PR,
meaning that a developer now defines variable with standard CRD
mechanisms and kubebuilder annotations, rather than defining the
manually constructed `VariableSchema` functions for each type
previously.

**Which issue(s) this PR fixes**:
Fixes #

**How Has This Been Tested?**:
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the tests.
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Depends on #536.

Author: jimmidyson

api/go.mod

@@ -7,43 +7,72 @@ go 1.21
 
 toolchain go1.22.2
 
+replace github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/common => ../common
+
 require (
+	github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/common v0.7.0
 	github.com/nutanix-cloud-native/prism-go-client v0.3.4
 	github.com/onsi/gomega v1.33.0
 	k8s.io/api v0.29.3
 	k8s.io/apiextensions-apiserver v0.29.3
 	k8s.io/apimachinery v0.29.3
-	k8s.io/utils v0.0.0-20231127182322-b307cd553661
 	sigs.k8s.io/cluster-api v1.7.0
 	sigs.k8s.io/controller-runtime v0.17.3
 )
 
 require (
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/blang/semver/v4 v4.0.0 // indirect
-	github.com/emicklei/go-restful/v3 v3.11.0 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
+	github.com/emicklei/go-restful/v3 v3.12.0 // indirect
+	github.com/evanphx/json-patch/v5 v5.9.0 // indirect
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/go-logr/logr v1.4.1 // indirect
 	github.com/go-openapi/jsonpointer v0.19.6 // indirect
 	github.com/go-openapi/jsonreference v0.20.2 // indirect
 	github.com/go-openapi/swag v0.22.3 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.4 // indirect
 	github.com/google/gnostic-models v0.6.8 // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/google/gofuzz v1.2.0 // indirect
+	github.com/google/uuid v1.4.0 // indirect
+	github.com/imdario/mergo v0.3.13 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
+	github.com/prometheus/client_golang v1.18.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.45.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/valyala/fastjson v1.6.4 // indirect
+	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
 	golang.org/x/net v0.24.0 // indirect
+	golang.org/x/oauth2 v0.18.0 // indirect
+	golang.org/x/sys v0.19.0 // indirect
+	golang.org/x/term v0.19.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
+	golang.org/x/time v0.5.0 // indirect
+	gomodules.xyz/jsonpatch/v2 v2.4.0 // indirect
+	google.golang.org/appengine v1.6.8 // indirect
 	google.golang.org/protobuf v1.33.0 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/client-go v0.29.3 // indirect
+	k8s.io/component-base v0.29.3 // indirect
 	k8s.io/klog/v2 v2.120.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
+	k8s.io/utils v0.0.0-20231127182322-b307cd553661 // indirect
 	sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.4.1 // indirect
+	sigs.k8s.io/yaml v1.4.0 // indirect
 )