Fix typo in README.md files in packages/cli and packages/vscode

[teamchong]

Description:
This PR fixes a typo in the README.md files located in the packages/cli and packages/vscode directories. The variable chema has been corrected to schema in both files.

Changes:

• Corrected the typo from chema to schema in both README.md files.

Closes #644

[teamchong]

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[pelikhan]

Thanks!