Add queryElement test helper function

[spectranaut]

This PR fulfills the request from issue #1403 to have a queryElement helper function that is analogous to queryElements. It also replaces all the calls of queryElements when only the first element is needed.

[jongund]

@spectranaut
How will this change effect current regression tests and the regression tests in pull requests?
Will there be linting to make using findElement failing?

[smhigley]

Now I'm wondering if I should have named queryElements to make it more obvious that it failed if no elements were found, and to differentiate more meaningfully from findElement(s) 😅.

This looks fine though. Is it mostly just to provide parity with queryElements, so test authors aren't confused?

[jongund]

How will this change effect current regression tests and the regression tests in pull request?
How will linting to make using findElement failing?

[spectranaut]

@smhigley yup! just for parity.

@jongund thanks for asking but I didn't add any new lint errors, and you can still use findElement. The goal was just to provide an API like queryElements called queryElement, because authors might expect it.

[mcking65]

OK, thank you @spectranaut and @smhigley, this seems ready to go. @jongund , it appears that it won't cause any disruption of work for you. I will merge.

[jongund]

Thank you for the status of how this change affects existing pull requests.

[jongund]

@spectranaut @smhigley
Is there plan to update all the regression tests to use only queryElements and queryElement?