docs: fix and improve documentation

[afsuyadi]

Issue : #306063

Full summary for every file fix:

1. .eslint-plugin-local/README.md - Line 3
   Error type: Subject-verb disagreement
   Before: Some example custom rules includes:
   After: Some example custom rules include:

2. .devcontainer/README.md - Line 45
   Error type: Redundant preposition ("under in")
   Before: You should see VNC web client (6080) under in the list of ports.
   After: You should see VNC web client (6080) in the list of ports.

3. .devcontainer/README.md - Line 71
   Error type: Missing word ("need to change")
   Before: You may also need change your VNC client's Picture Quality setting
   After: You may also need to change your VNC client's Picture Quality setting

4. build/monaco/README-npm.md - Line 6
   Error type: Wrong plural form ("languages supports")
   Before: that contains this module and adds languages supports.
   After: that contains this module and adds language support.

5. extensions/json-language-features/CONTRIBUTING.md - Multiple lines
   Error type: Missing space before '[' hyperlink
   Before: with a single window with themulti-root workspace
   After: with a single window with the multi-root workspace

6. extensions/css-language-features/CONTRIBUTING.md — Multiple lines
   Error type: Missing space before backtick
   Before: setting breakpoints in\css-language-features/client/ After: setting breakpoints in \css-language-features/client/

[vs-code-engineering]

📬 CODENOTIFY

The following users are being notified based on files changed in this PR:

@bpasero

Matched files:

• src/vs/platform/files/node/watcher/parcel/parcelWatcher.ts
• src/vs/workbench/contrib/files/browser/explorerViewlet.ts
• src/vs/workbench/contrib/files/browser/views/explorerViewer.ts

[afsuyadi]

Hello, @mjbvz please review my pull request. Thanks a lot..