fix(curriculum): changed test text to use should for Front End Libraries

[RandellDawson]

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Related to PR #36860

This PR makes sure all challenges' tests in the Front End Libraries section use "should " or "should not".

[gitpod-io]

[RandellDawson]

@moT01 I have committed your suggested changes.

[moT01]

🎉 LGTM 🎉

[cmccormack]

These all look good to me; however, I would have preferred to have you and your removed from most of the comments as it seems a bit personal.

For example:

- text: You should add an <code>i</code> element with the classes <code>fas</code> and <code>fa-thumbs-up</code>.

could be rewritten

- text: An <code>i</code> element with the classes <code>fas</code> and <code>fa-thumbs-up</code> should be added.

Again, this looks good to me and I approve as-is, if you agree with what I stated above I could do the work to go through them again, just let me know.

[Manish-Giri]

LGTM 💯

[RandellDawson]

@cmccormack According to the current Writing challenge descriptions/instructions section, the challenge text should be written using the second person "you" and most of the tests in the curriculum seem to be written this way. I do not think it necessary, but you can create a separate issue where we can all discuss it I suppose. In the mean time, I think this PR can be merged now.

[ojeytonwilliams]

I agree that there's no need to hold this up pending a change in the style guide.