chore: Remove test INFURA_KEY

[yagopv]

What it solves

We are removing the INFURA_KEY in the protocol-kit and the api-kit.

We are using public RPC nodes instead of Infura.

We added Sepolia chain to our protocol-kit tests.

Advantages:

• Removing dependencies and secrets
• Allowing external PR's to execute tests as cannot access Github secrets for security reasons

[coveralls]

Pull Request Test Coverage Report for Build 7246363597

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• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+18.6%) to 100.0%

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Totals
Change from base Build 7222021252:	18.6%
Covered Lines:	25
Relevant Lines:	25

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💛 - Coveralls