Adds L2EP Linea integration support

[mohamed-mehany]

Description

This PR adds the layer 2 sequencer health external adapter logic for Linea.

Changes

• Adds Linea layer 2 sequencer health adapter

Motivation

INTAUTO-214

Steps to Test

1. Unit tests
2. Ran the adapter locally and ran the request to check Linea sequencer health.

export adapter=layer2-sequencer-health 
yarn test $adapter/test/integration

Quality Assurance

• If a new adapter was made, or an existing one was modified so that its environment variables have changed, update the relevant infra-k8s configuration file.
• https://github.com/smartcontractkit/infra-k8s/pull/22084
• If a new adapter was made, or an existing one was modified so that its environment variables have changed, update the relevant adapter-secrets configuration file or update the soak testing blacklist.
• If a new adapter was made, or a new endpoint was added, update the test-payload.json file with relevant requests.
• The branch naming follows git flow (feature/x, chore/x, release/x, hotfix/x, fix/x) or is created from Jira.
• This is related to a maximum of one Jira story or GitHub issue.
• Types are safe (avoid TypeScript/TSLint features like any and disable, instead use more specific types).
• All code changes have 100% unit and integration test coverage. If testing is not applicable or too difficult to justify doing, the reasoning should be documented explicitly in the PR.

INTAUTO-214)

[changeset-bot]

🦋 Changeset detected

Latest commit: 5c16b46

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@chainlink/layer2-sequencer-health-adapter	Minor

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[mxiao-cll]

You linked the wrong infra-k8s PR

[mohamed-mehany]

You linked the wrong infra-k8s PR

Thanks for the review.
Good catch, will fix.