docs: Updating docs for e2e tests

[bisakhmondal]

Please answer these questions before submitting a pull request

• Why submit this pull request?

• Bugfix

• New feature provided

• Improve performance

• Backport patches

• Related issues
  closes Doc: a better doc about how to write and run e2e test and unit test for Backend #1303
  closes docker-compose building apisix image is failing (for e2e backend test) #1581

Changes made:

• New doc introducing how to write e2e & unit tests.
• Merged the back-end-e2e.md doc with back-end-tests.md along with updating the contents.
• a script to automate setting up the environment for e2e tests.

Thanks :)

[codecov-io]

Codecov Report

Merging #1625 (77b7c47) into master (1ba32d9) will decrease coverage by 0.41%.
The diff coverage is n/a.

❗ Current head 77b7c47 differs from pull request most recent head 429253e. Consider uploading reports for the commit 429253e to get more accurate results

@@            Coverage Diff             @@
##           master    #1625      +/-   ##
==========================================
- Coverage   71.69%   71.27%   -0.42%     
==========================================
  Files         133       47      -86     
  Lines        5469     3116    -2353     
  Branches      592        0     -592     
==========================================
- Hits         3921     2221    -1700     
+ Misses       1305      652     -653     
  Partials      243      243              

Flag	Coverage Δ
backend-e2e-test	62.13% <ø> (+0.38%)	⬆️
backend-e2e-test-ginkgo	47.65% <ø> (-0.21%)	⬇️
backend-unit-test	51.77% <ø> (-0.04%)	⬇️
frontend-e2e-test	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
api/internal/core/store/store.go	86.14% <0.00%> (-1.81%)	⬇️
api/internal/utils/closer.go	33.33% <0.00%> (ø)
api/internal/handler/ssl/ssl.go	73.29% <0.00%> (ø)
api/internal/handler/data_loader/route_export.go	69.17% <0.00%> (ø)
api/internal/handler/data_loader/route_import.go	64.91% <0.00%> (ø)
web/src/pages/Consumer/Create.tsx
web/src/pages/Upstream/transform.ts
...eb/src/components/PluginOrchestration/constants.ts
...ages/Route/components/Step2/RequestRewriteView.tsx
web/src/pages/Route/constants.ts
... and 84 more

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[bisakhmondal]

cc @nic-chen, @juzhiyuan to review when you have time :)

Guys, please suggest me a markdown linter, it seems mine is not working😄

[nic-chen]

could we put the content of back-end-e2e.md into back-end-tests.md?

[bisakhmondal]

Thanks, @nic-chen for fixing the lint :) It's really helpful. Definitely! we can merge these docs together.

[starsz]

Pretty good.Thank you for your contribution.

[juzhiyuan]

LGTM

[juzhiyuan]

Don't forget to update this file:

apisix-dashboard/docs/en/latest/config.json

Line 17 in 429253e

"items": ["develop", "I18N_USER_GUIDE", "front-end-e2e", "back-end-e2e"]

[nic-chen]

ping @starsz @gxthrj

[Jaycean]

LGTM. Thks.

[nic-chen]

merged. thanks a lot. @bisakhmondal

[bisakhmondal]

😁 Thank you, everyone, for such wonderful quick reviews. V2.5 💪