migrate(postgresql): move to incubator (#12238)

**Description**
Move postgresql to incubator as it is currently not functional.
⚒️ Fixes  # 

**⚙️ 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

**🧪 How Has This Been Tested?**

**📃 Notes:**

**✔️ 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/incubator/postgresql/Chart.yaml

@@ -6,7 +6,7 @@ dependencies:
     version: 14.0.1
 deprecated: false
 description: PostgresSQL
-home: https://truecharts.org/charts/stable/postgresql
+home: https://truecharts.org/charts/incubator/postgresql
 icon: https://truecharts.org/img/hotlink-ok/chart-icons/postgresql.png
 keywords:
   - postgres
@@ -20,7 +20,7 @@ maintainers:
     url: https://truecharts.org
 name: postgresql
 sources:
-  - https://github.com/truecharts/charts/tree/master/charts/stable/postgresql
+  - https://github.com/truecharts/charts/tree/master/charts/incubator/postgresql
   - https://www.postgresql.org/
 type: application
 version: 14.0.0