Upgrade Typescript Components to TS 3.7

[jbuckner]

Task Details

We are currently on Typescript 3.6 and with Typescript 3.7, we get optional chaining and null coalescing operators. The optional chaining in particular will allow us to reduce a lot of code from

if (foo) {
  foo.bar()
}

to

foo?.bar()

Verification

TypeScript is updated in package.json. Spots that can be optionally chained should be switched to use optional chaining. All tests should pass.

Stakeholders

@jbuckner

[maze-runnar]

@jbuckner I want to work on this issue.

[maze-runnar]

@jbuckner, I am a GSoC aspirant and looking for contributions to this project. I am good in react, python(Flask, Django) and javaScript. I have seen the projects list and personally want to work on https://github.com/internetarchive/iaux/projects/2. I have good knowledge and experience in UI/UX.
I am a core contributor(50+ pull Requests) in https://github.com/fossasia/open-event-frontend, which is mainly a fully UI/UX oriented and Uses Semantic UI. I want to get started with this project for this year's GSoC can you please Guide me for choosing an idea regarding to my domain.

[mhk19]

@jbuckner i want to work on this issue