chore(helm): update image chronograf digest to 2f9ef13 (#35608)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| chronograf | digest | `f6ef785` -> `2f9ef13` |

Add the preset `:preserveSemverRanges` to your config if you don't want
to pin your dependencies.

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charts/stable/chronograf/Chart.yaml

@@ -36,5 +36,5 @@ sources:
   - https://hub.docker.com/_/chronograf
   - https://www.influxdata.com/time-series-platform/chronograf/
 type: application
-version: 7.5.8
+version: 7.5.9
 

charts/stable/chronograf/values.yaml

@@ -1,7 +1,7 @@
 image:
   pullPolicy: IfNotPresent
   repository: chronograf
-  tag: latest@sha256:f6ef7852b2257d0e7756589757627a50d2bb6ce74c4abf3c7e4297483f52b7f8
+  tag: latest@sha256:2f9ef13b8c81d8760a2566135b198a6244a8609581760591ff16b35982245f1c
 persistence:
   chronograf:
     enabled: true