Add local provider support for compaction

[abdasgupta]

How to categorize this PR?

/area control-plane
/kind bug

What this PR does / why we need it:
This PR fixes the bug that was not letting the compaction job use local storage. Without this PR, compaction jobs were not running for gardener local setup with local provider.

Which issue(s) this PR fixes:
Fixes #709

Special notes for your reviewer:

Release note:

Local storage provider for backups is now supported for snapshot compaction jobs.

[abdasgupta]

/test pull-etcd-druid-e2e-kind-alpha-features

[abdasgupta]

/test pull-etcd-druid-e2e-kind

[shreyas-s-rao]

@abdasgupta thanks for the PR. I have a few comments. Please address them. Additionally, you might also need to use an init container to change file permissions for the store provider directories, as seen here:

etcd-druid/controllers/etcdcopybackupstask/reconciler.go

Lines 365 to 383 in 0477a27

	if r.Config.FeatureGates[features.UseEtcdWrapper] {
	if targetProvider == druidutils.Local {
	// init container to change file permissions of the folders used as store to 65532 (nonroot)
	// used only with local provider
	job.Spec.Template.Spec.InitContainers = []corev1.Container{
	{
	Name: "change-backup-bucket-permissions",
	Image: "alpine:3.18.2",
	Command: []string{"sh", "-c", "--"},
	Args: []string{fmt.Sprintf("%s%s%s%s", "chown -R 65532:65532 /home/nonroot/", *targetStore.Container, " /home/nonroot/", *sourceStore.Container)},
	VolumeMounts: volumeMounts,
	SecurityContext: &corev1.SecurityContext{
	RunAsGroup: pointer.Int64(0),
	RunAsNonRoot: pointer.Bool(false),
	RunAsUser: pointer.Int64(0),
	},
	},
	}
	}

You may consult with @aaronfern for help with this.

[aaronfern]

Compaction job would not need an init container as it used an emptyDir volume, and that's fresh for every run, so no permission change is needed

[abdasgupta]

/test pull-etcd-druid-e2e-kind

[abdasgupta]

/test pull-etcd-druid-e2e-kind

[shreyas-s-rao]

@abdasgupta thanks for making the requested changes. Overall looks good, except for couple of nits. PTAL, thanks

[shreyas-s-rao]

/lgtm