Fix bad quote characters in mobile docs

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 7.0.x
• Component/s: Mobile Infrastructure, Screens
• Labels: None
• Git Pull Request: https://github.com/sez11a/liferay-docs/pull/2887

Change curved quotes to straight quotes in mobile docs. Curved quotes are rendered incorrectly in the customer portal.