Sync LuigiClient API on LuigiElement Typescript declaration with actu…

[amilewskaa]

Description

Changes proposed in this pull request:

• Sync LuigiClient API on LuigiElement Typescript declaration with actual implementation

Related issue(s)

#3880

[walmazacn]

LGTM 👍

[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
2 out of 4 committers have signed the CLA.

✅ walmazacn
✅ JohannesDoberer
❌ Anna Milewska
❌ smahati

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