chore(deps): update pepr to v0.28.6 (#300)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[registry1.dso.mil/ironbank/opensource/defenseunicorns/pepr/controller](https://github.com/defenseunicorns/pepr)
([source](https://repo1.dso.mil/dsop/opensource/defenseunicorns/pepr/controller))
| patch | `v0.28.3` -> `v0.28.6` |

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tasks/create.yaml

@@ -4,7 +4,7 @@ variables:
 
   - name: REGISTRY1_PEPR_IMAGE
     # renovate: datasource=docker versioning=semver
-    default: registry1.dso.mil/ironbank/opensource/defenseunicorns/pepr/controller:v0.28.3
+    default: registry1.dso.mil/ironbank/opensource/defenseunicorns/pepr/controller:v0.28.6
 
 tasks:
   - name: standard-package