Description of problem:

SRE utilized `mapi_current_pending_csr` to help alert on specific conditions. We are encountering false positives as this metric is present and of a positive integer when no CSRs exist on the cluster. 


How reproducible:
We have encountered a few false positives across our fleet.


Steps to Reproduce:
1.TBA
2.
3.

Actual results:

```
[~ {production} (cluster:default)]$ oc get csr -A
No resources found
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver exec deploy/machine-approver -- curl http://127.0.0.1:9191/metrics | grep mapi
Defaulting container name to kube-rbac-proxy.
Use 'oc describe pod/machine-approver-757975f664-rhq5x -n openshift-cluster-machine-approver' to see all of the containers in this pod.
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0# HELP mapi_current_pending_csr Count of pending CSRs at the cluster level
# TYPE mapi_current_pending_csr gauge
mapi_current_pending_csr 3
# HELP mapi_max_pending_csr Threshold value of the pending CSRs beyond which any new CSR requests will be ignored
# TYPE mapi_max_pending_csr gauge
mapi_max_pending_csr 107
100  195k    0  195k    0     0  63.4M      0 --:--:-- --:--:-- --:--:-- 63.4M

```

Expected results:
```
[~ {production} (cluster:default)]$ oc get csr -A
No resources found
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver exec deploy/machine-approver -- curl http://127.0.0.1:9191/metrics | grep mapi
Defaulting container name to kube-rbac-proxy.
Use 'oc describe pod/machine-approver-757975f664-rhq5x -n openshift-cluster-machine-approver' to see all of the containers in this pod.
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0# HELP mapi_current_pending_csr Count of pending CSRs at the cluster level
# TYPE mapi_current_pending_csr gauge
mapi_current_pending_csr 0
# HELP mapi_max_pending_csr Threshold value of the pending CSRs beyond which any new CSR requests will be ignored
# TYPE mapi_max_pending_csr gauge
mapi_max_pending_csr 107
100  195k    0  195k    0     0  63.4M      0 --:--:-- --:--:-- --:--:-- 63.4M


Additional info:
It may be the controller caching. The metric becomes accurate after deleting the pod. 

```
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver exec deploy/machine-approver -- curl http://127.0.0.1:9191/metrics | grep mapi
Defaulting container name to kube-rbac-proxy.
Use 'oc describe pod/machine-approver-757975f664-rhq5x -n openshift-cluster-machine-approver' to see all of the containers in this pod.
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0# HELP mapi_current_pending_csr Count of pending CSRs at the cluster level
# TYPE mapi_current_pending_csr gauge
mapi_current_pending_csr 3
# HELP mapi_max_pending_csr Threshold value of the pending CSRs beyond which any new CSR requests will be ignored
# TYPE mapi_max_pending_csr gauge
mapi_max_pending_csr 107
100  195k    0  195k    0     0  63.4M      0 --:--:-- --:--:-- --:--:-- 63.4M
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver get pods
NAME                                READY   STATUS    RESTARTS   AGE
machine-approver-757975f664-rhq5x   2/2     Running   5          44h
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver delete pod machine-approver-757975f664-rhq5x
pod "machine-approver-757975f664-rhq5x" deleted
^C
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver get pods
NAME                                READY   STATUS              RESTARTS   AGE
machine-approver-757975f664-94gjz   0/2     ContainerCreating   0          8s
machine-approver-757975f664-rhq5x   0/2     Terminating         5          45h
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver get pods
NAME                                READY   STATUS    RESTARTS   AGE
machine-approver-757975f664-94gjz   2/2     Running   0          18s
[~ {production} (cluster:default)]$ oc -n openshift-cluster-machine-approver exec deploy/machine-approver -- curl http://127.0.0.1:9191/metrics | grep mapi
Defaulting container name to kube-rbac-proxy.
Use 'oc describe pod/machine-approver-757975f664-94gjz -n openshift-cluster-machine-approver' to see all of the containers in this pod.
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0# HELP mapi_current_pending_csr Count of pending CSRs at the cluster level
# TYPE mapi_current_pending_csr gauge
mapi_current_pending_csr 0
# HELP mapi_max_pending_csr Threshold value of the pending CSRs beyond which any new CSR requests will be ignored
# TYPE mapi_max_pending_csr gauge
mapi_max_pending_csr 0
100  188k    0  188k    0     0  30.7M      0 --:--:-- --:--:-- --:--:-- 30.7M
```