[release/v2.21] Use seed config proxy for seed-cm (#11561)

[mate4st]

What this PR does / why we need it:

Backport of:
#11561

Which issue(s) this PR fixes:

Fixes #11509

What type of PR is this?

/kind bug

Use seed proxy configuration for seed-controler-manager

NONE

[mate4st]

/test pre-kubermatic-test-integration

[mate4st]

/test pre-kubermatic-test-integration

[xrstf]

/approve
/lgtm
/override pre-kubermatic-test-integration
/override pre-kubermatic-mla-e2e

[kubermatic-bot]

LGTM label has been added.

Git tree hash: c53c5788cfd304199e19968f6983b8b8636581b5

[kubermatic-bot]

@xrstf: Overrode contexts on behalf of xrstf: pre-kubermatic-mla-e2e, pre-kubermatic-test-integration

In response to this:

/approve
/lgtm
/override pre-kubermatic-test-integration
/override pre-kubermatic-mla-e2e

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[embik]

/approve

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: embik, WeirdMachine, xrstf

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• pkg/controller/OWNERS [embik,xrstf]

Approvers can indicate their approval by writing /approve in a comment
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[mate4st]

/cherrypick release/v2.20

[kubermatic-bot]

@WeirdMachine: #11596 failed to apply on top of branch "release/v2.20":

Applying: Use seed config proxy for seed-cm (#11561)
Using index info to reconstruct a base tree...
M	pkg/controller/operator/common/util.go
A	pkg/controller/operator/common/webhook.go
M	pkg/controller/operator/master/resources/kubermatic/api.go
M	pkg/controller/operator/master/resources/kubermatic/master-controller-manager.go
M	pkg/controller/operator/master/resources/kubermatic/ui.go
M	pkg/controller/operator/seed/resources/kubermatic/seed-controller-manager.go
Falling back to patching base and 3-way merge...
Auto-merging pkg/controller/operator/seed/resources/kubermatic/seed-controller-manager.go
Auto-merging pkg/controller/operator/master/resources/kubermatic/ui.go
Auto-merging pkg/controller/operator/master/resources/kubermatic/master-controller-manager.go
Auto-merging pkg/controller/operator/master/resources/kubermatic/api.go
CONFLICT (modify/delete): pkg/controller/operator/common/webhook.go deleted in HEAD and modified in Use seed config proxy for seed-cm (#11561). Version Use seed config proxy for seed-cm (#11561) of pkg/controller/operator/common/webhook.go left in tree.
Auto-merging pkg/controller/operator/common/util.go
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 Use seed config proxy for seed-cm (#11561)
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherrypick release/v2.20

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.