How to disable WebStorm semicolon check?

1. Settings/Preferences | Editor | Inspections
2. JavaScript | Code style issues | Unterminated statement — disable this inspection

You can also reach the same inspection by:

1. Placing caret on problematic place in your Editor and bringing Quick Fix menu (Alt + Enter or by clicking on light bulb icon)
2. Choosing right option in appeared menu (if not sure which one then try step #3 for few of them)
3. Arrow Right (or click on small triangle on the right side) to open submenu
4. Choose desired action

P.S.
JSLinh/JSHint and alike may also produce such warnings if you are using these tools.

As for the actual code generated by IDE (e.g. when using Code | Reformat... or using code completion popup/functionality) — such option is available at

• Settings/Preferences | Editor | Code Style | JavaScript (similar path for TypeScript)
• Punctuation tab