feat(docuseal): Add Docuseal

[SolidSly]

Description

⚒️ Fixes #

It solves #21452.

It is possible to use an external psql database. However, I think it is a little over complicated for no real need beside if you are a company with many users. At the moment, this Helm chart supports sqlite by default.
It is possible to use an external database by adding a custom environment variable (cf link).

⚙️ 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?

Tested locally using Helm commands, on a TrueNAS system.

📃 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
• I made sure the title starts with feat(chart-name):, fix(chart-name): or chore(chart-name):

➕ App addition

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

• 🖼️ I have added an icon in the Chart's root directory called icon.png

There is no icon.png in Chart folder, but webp images. I added them for this Helm chart.

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[SolidSly]

This PR will be closed as it is not possible to add new Helm chart currently (cf link).

[stavros-k]

Please see #21452 (comment)

[stavros-k]

CNPG must be added considering the app supports postgres.
https://github.com/docusealco/docuseal/blob/6d9311699336136eac3a0489398208b39a296c37/docker-compose.yml#L15

[SolidSly]

It should be working fine now. CNPG has been included too.

Added CNPG and reviewed