Open sidebar after user creates a new item in boards [RUN AS-IF-FOSS]

What does this MR do and why?

Open sidebar after user creates a new item in boards (issue boards and epic boards). This is a regression introduced when refactoring boards to GraphQL.

Screenshots or screen recordings

Before	After
Screen_Recording_2021-03-24_at_10.00.41_AM	Screen_Recording_2021-03-24_at_10.01.32_AM

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #323446 (closed)