Delete Soak test and related code

[dskloetc]

Description

The soak test has been disabled for over 6 months and had been failing for many months before that.
It has a lot of scripts, some of which have failing tests, which causes a maintenance burden.

Changes

1. Remove soak test workflows.
2. Delete from packages/scripts/src:
   1. adapter-dependencies
   2. docker-build
   3. ephemeral-adapters
   4. flux-emulator
   5. get-changed-adapters
   6. schema-flatten
3. Remove deleted scripts from scripts section of package.json.
4. Remove deleted scripts from pattern of tests that fail or don't compile.
5. Delete packages/k6
6. Remove mention of soak test from CONTRIBUTING.md.
7. Remove mention of soak test from PR description template.
8. Ran yarn.

Steps to Test

N/A

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.
• 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.

[changeset-bot]

🦋 Changeset detected

Latest commit: 275f5a5

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

This PR includes changesets to release 1 package

Name	Type
@chainlink/ea-scripts	Minor

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[mxiao-cll]

Can also delete the adapter-secrets repo

[dskloetc]

Can also delete the adapter-secrets repo

I'm not familiar with this.