Adding Spanish translation

[amatosg]

Also added missing translation strings.

Relates to #28

Description

Many translations where missing. This PR adds full Spanish translations and adds translation strings for German (not translated yet)

Type of change

• Spanish Translation

🧪 How Has This Been Tested?

Every single pages was opened and filed were selected to verify the translation is not missing

Checklist:

• Verified output manually
• Tested with relevant sample documents or data

Expected Results:

• all pages should be shown in Spanish

Actual Results:

• Pages were shown in Spanish :)

Checklist:

• I have signed the Contributor License Agreement (CLA) or my organization has signed the Corporate CLA
• 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 that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[github-actions]

All contributors have signed the CLA ✍️ ✅
_{Posted by the CLA Assistant Lite bot.}

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GitGuardian id	GitGuardian status	Secret	Commit	Filename
-	-	Generic Password	daeb343	public/locales/es/common.json	View secret

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[amatosg]

I have read the CLA Document and I hereby sign the CLA

[amatosg]

although I see #266, this PR adds missing translation strings