[CI] Add CI Troubleshooting doc

[unlikelyzero]

Closes #4576

Describe your changes:

• Documents how to bust cache
• Update flakiness docs
• How to run CI locally
• Update code coverage document

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Is this change backwards compatible? For example, developers won't need to change how they are calling the API or how they've extended core plugins such as Tables or Plots.

Author Checklist

• Changes address original issue?
• Tests included and/or updated with changes?
• Command line build passes?
• Has this been smoke tested?
• Testing instructions included in associated issue OR is this a dependency/testcase change?

Reviewer Checklist

• Changes appear to address issue?
• Reviewer has tested changes by following the provided instructions?
• Changes appear not to be breaking changes?
• Appropriate automated tests included?
• Code style and in-line documentation are appropriate?
• Has associated issue been labelled unverified? (only applicable if this PR closes the issue)
• Has associated issue been labelled bug? (only applicable if this PR is for a bug fix)

[deploysentinel]

Current Playwright Test Results Summary

✅ 153 Passing - ⚠️ 3 Flaky

Run may still be in progress, this comment will be updated as current testing workflow or job completes...

(Last updated on 11/09/2023 04:15:43pm UTC)

Run Details

Running Job e2e-stable on CircleCI

Commit: 8967b6a

Started: 11/09/2023 04:06:33pm UTC

⚠️ Flakes

📄   functional/plugins/plot/logPlot.e2e.spec.js • 1 Flake

Test Case Results

Test Case	Last 7 days Failures	Last 7 days Flakes
Log plot tests Log Plot ticks are functionally correct in regular and log mode and after refresh Retry 2 • Retry 1 • Initial Attempt	1.27% (2) 2 / 158 runs failed over last 7 days	32.28% (51) 51 / 158 runs flaked over last 7 days

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📄   functional/plugins/timer/timer.e2e.spec.js • 1 Flake

Test Case Results

Test Case	Last 7 days Failures	Last 7 days Flakes
Timer Can perform actions on the Timer Retry 1 • Initial Attempt	0% (0) 0 / 157 runs failed over last 7 days	11.46% (18) 18 / 157 runs flaked over last 7 days

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📄   functional/plugins/notebook/notebookSnapshots.e2e.spec.js • 1 Flake

Test Case Results

Test Case	Last 7 days Failures	Last 7 days Flakes
Snapshot image tests Can drop an image onto a notebook and create a new entry Retry 1 • Initial Attempt	0% (0) 0 / 161 runs failed over last 7 days	68.32% (110) 110 / 161 runs flaked over last 7 days

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View Detailed Build Results

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[codecov]

Codecov Report

Merging #6988 (f9c6e82) into master (3c933ea) will decrease coverage by 3.35%.
Report is 1 commits behind head on master.
The diff coverage is n/a.

❗ Current head f9c6e82 differs from pull request most recent head 8967b6a. Consider uploading reports for the commit 8967b6a to get more accurate results

@@            Coverage Diff             @@
##           master    #6988      +/-   ##
==========================================
- Coverage   56.08%   52.74%   -3.35%     
==========================================
  Files         652      652              
  Lines       26178    26253      +75     
  Branches     2525     2525              
==========================================
- Hits        14683    13846     -837     
- Misses      10796    11710     +914     
+ Partials      699      697       -2     

Flag	Coverage Δ		*Carryforward flag
e2e-full	41.92% <ø> (+0.12%)	⬆️	Carriedforward from 21d8482
e2e-stable	39.52% <ø> (-18.51%)	⬇️
unit	49.00% <ø> (-0.49%)	⬇️

*This pull request uses carry forward flags. Click here to find out more.

see 128 files with indirect coverage changes

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[unlikelyzero]

@ozyx please review

[ozyx]

Just some typos and grammatical stuff but this is looking great overall. Really nice to have the codecov process documented!