Add devcontainer support

[JohnNiang]

What type of PR is this?

/kind improvement /area core

What this PR does / why we need it:

This PR adds devcontainer support for a better development experience.

Does this PR introduce a user-facing change?

None

[f2c-ci-robot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 58.06%. Comparing base (bc10336) to head (b83e560). Report is 56 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #6252 +/- ## ============================================ + Coverage 54.51% 58.06% +3.55% - Complexity 3523 3757 +234 ============================================ Files 646 648 +2 Lines 21862 22014 +152 Branches 1528 1547 +19 ============================================ + Hits 11917 12782 +865 + Misses 9328 8612 -716 - Partials 617 620 +3 ```

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[ruibaby]

是不是配置一下 extensions 字段？比如添加 VSCode 的 Java Pack、Vue Official、EditorConfig、ESlint 这些所需插件。