fix: increase max gas price allowed by default

[mpetrun5]

Set max gas price by default to be 500gwei. It won't be that much as it uses estimate gas price but that is the maximum.
If we want to change on mainnet it is easy to set it in the config.
All the other configurations seem reasonable.

Before it was 20 gwei and tx wouldn't appear on mumbai and goerli when the networks were congested.

Description

Related Issue Or Context

Closes: #132

How Has This Been Tested? Testing details.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation

Checklist:

• I have commented my code, particularly in hard-to-understand areas.
• I have ensured that all acceptance criteria (or expected behavior) from issue are met
• I have updated the documentation locally and in docs.
• I have added tests to cover my changes.
• I have ensured that all the checks are passing and green, I've signed the CLA bot

[github-actions]

Go Test coverage is 67.1 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 67.0 %\ ✨ ✨ ✨