HEHA-315 Weather: accept 0 as a temperature

[jackdclark]

What does this PR do? (please provide any background)

We don't render a temperature when it's 0 because JS evaluates 0 as falsy

What tests does this PR have?

Added a regression test for this in weather-test.jsx

How can this be tested?

npm run docs & check http://localhost:4000/#weather, I've conveniently added an example with 0 to see it working

Screenshots / Screencast

What gif best describes how you feel about this work?

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• [x] I have checked our general contributing document and the project specific contributing document (if present) and I'm happy for this to be reviewed.

  Reviewers

Review 1

• [x] :+1:

Review 2 *

• [x] :+1:

Review 3 (optional)

• [ ] :+1:

By adding a +1 you are confirming you have...

• Witnessed the work behaving as expected (this could be on the author's machine or screencast).
• Checked for coding anti-patterns.
• Checked for appropriate test coverage.
• Checked all the tests are passing.

* for HX this review must be completed by an SE, SA or Project Guru

[rahulpatel]

Taking :two:

[rahulpatel]

Looking good! :+1:

[elliottcrush]

I suppose so. :+1: