feat: implement transaction monitor

[mpetrun5]

Implement transaction monitor that sends transactions and resends them with higher gas if they are stuck.

Description

Related Issue Or Context

Closes: #338

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 chainbridge-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

[mpetrun5]

Still want to test somewhere there is London gas price because I suspect the tip can be 1 and after the increase it would still be 1 and it won't go through because it is the same.

[github-actions]

Go Test coverage is 63.7 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 63.6 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 63.7 %\ ✨ ✨ ✨

[github-actions]

Go Test coverage is 63.7 %\ ✨ ✨ ✨

[P1sar]

In general looks good, left couple comments to check.

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ mpetrun5
❌ Matija Petrunic

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[github-actions]

Go Test coverage is 63.7 %\ ✨ ✨ ✨