Perfect the codebase for wamr-ide (#1817)

Fix errors and warnings reported by eslint
Add CONTRIBUTING document for vscode-extension

test-tools/wamr-ide/VSCode-Extension/CONTRIBUTING.md

@@ -0,0 +1,34 @@
+# CONTRIBUTING
+
+## Pull requests
+
+To submit your change:
+
+-   Make sure your code is in line with our
+    [coding conventions](##Coding-conventions).
+-   Create an [issue] describing the bug the PR fixes or the feature you intend
+    to implement.
+-   Submit a [pull request] into the main branch.
+
+## Coding conventions
+
+#### Format
+
+The codebase is formatted by `Prettier` and the `.prettierrc.json` has been
+configured.
+
+-   VSCode along with `Format on Save` configuration could easily format your
+    code during development.
+-   You can run `prettier-format-check` and `prettier-format-apply` to check and
+    format your codebase with `prettier` in terminal.
+
+#### Lint
+
+`ESlint` is used as linter for the codebase and the `.eslintrc.json` has been
+configured.
+
+-   It's suggested to run `npm run lint` then fix errors and warnings before
+    committing.
+
+[issue]: https://github.com/bytecodealliance/wasm-micro-runtime/issues
+[pull request]: https://github.com/bytecodealliance/wasm-micro-runtime/pulls