Remove deprecated object metrics

[hasithsen]

Suspend and readiness metrics recording removed from GitRepository, Bucket, HelmRepository, HelmChart and OCIRepository reconcilers.

Refer fluxcd/flux2#5083.

[darkowlzz]

Thanks for working on this.

For verification, the following metrics were exported before:

# HELP gotk_reconcile_condition The current condition status of a GitOps Toolkit resource reconciliation.
# TYPE gotk_reconcile_condition gauge
gotk_reconcile_condition{kind="GitRepository",name="podinfo",namespace="default",status="False",type="Ready"} 0
gotk_reconcile_condition{kind="GitRepository",name="podinfo",namespace="default",status="True",type="Ready"} 1
gotk_reconcile_condition{kind="GitRepository",name="podinfo",namespace="default",status="Unknown",type="Ready"} 0
# HELP gotk_reconcile_duration_seconds The duration in seconds of a GitOps Toolkit resource reconciliation.
# TYPE gotk_reconcile_duration_seconds histogram
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.01"} 0
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.038363583488692544"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.1471764538093883"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.5646216173286169"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="2.166090855590701"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="8.309900738254731"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="31.879757075478317"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="122.30217221643493"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="469.19495946736544"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="1799.9999999999986"} 2
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="+Inf"} 2
gotk_reconcile_duration_seconds_sum{kind="GitRepository",name="podinfo",namespace="default"} 1.527162905
gotk_reconcile_duration_seconds_count{kind="GitRepository",name="podinfo",namespace="default"} 2
# HELP gotk_suspend_status The current suspend status of a GitOps Toolkit resource.
# TYPE gotk_suspend_status gauge
gotk_suspend_status{kind="GitRepository",name="podinfo",namespace="default"} 0

With this change, only the duration metrics are exported

# HELP gotk_reconcile_duration_seconds The duration in seconds of a GitOps Toolkit resource reconciliation.
# TYPE gotk_reconcile_duration_seconds histogram
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.01"} 0
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.038363583488692544"} 0
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.1471764538093883"} 0
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="0.5646216173286169"} 0
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="2.166090855590701"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="8.309900738254731"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="31.879757075478317"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="122.30217221643493"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="469.19495946736544"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="1799.9999999999986"} 1
gotk_reconcile_duration_seconds_bucket{kind="GitRepository",name="podinfo",namespace="default",le="+Inf"} 1
gotk_reconcile_duration_seconds_sum{kind="GitRepository",name="podinfo",namespace="default"} 0.737681252
gotk_reconcile_duration_seconds_count{kind="GitRepository",name="podinfo",namespace="default"} 1

LGTM!

[darkowlzz]

@hasithsen it would be nice to rebase to have just one commit here before we merge it, removing the merge branch commit.
Do it if you can. Otherwise, I'll rebase it myself before merge.