fix(external-service): don't use slices on scale and dont hardcode ta… (#8128)

…rgetPort

**Description**
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⚒️ Fixes  #8063

This, along with the common code addition, should fix the issues, just
need a quick confirmation after released

**⚙️ Type of change**

- [ ] ⚙️ Feature/App addition
- [ ] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code

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**✔️ Checklist:**

- [ ] ⚖️ My code follows the style guidelines of this project
- [ ] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
areas
- [ ] 📄 I have made corresponding changes to the documentation
- [ ] ⚠️ My changes generate no new warnings
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [ ] ⬆️ I increased versions for any altered app according to semantic
versioning

**➕ App addition**

If this PR is an app addition please make sure you have done the
following.

- [ ] 🪞 I have opened a PR on
[truecharts/containers](https://github.com/truecharts/containers) adding
the container to TrueCharts mirror repo.
- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

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charts/stable/external-service/Chart.yaml

@@ -3,7 +3,7 @@ appVersion: "latest"
 dependencies:
   - name: common
     repository: https://library-charts.truecharts.org
-    version: 12.4.21
+    version: 12.5.1
 deprecated: false
 description: Allow external services to be used like Apps.
 home: https://truecharts.org/charts/stable/external-service
@@ -20,7 +20,7 @@ name: external-service
 sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/external-service
 type: application
-version: 9.0.7
+version: 9.0.8
 annotations:
   truecharts.org/catagories: |
     - networking

charts/stable/external-service/values.yaml

@@ -8,11 +8,13 @@ service:
   main:
     type: ExternalIP
     externalIP: "1.1.1.1"
+    useSlice: false
     ports:
       main:
         protocol: https
         port: 10003
-        targetPort: 443
+        # Target port is the port of the "external service"
+        # Defaults to "port" if not set
 
 workload:
   main: