feat(checks): normalize check options to alway be an object

[straker]

Ensured check options is always an object and normalized any non-objects to be { value: param }. Also ensured each check was passed a merged result of the check default options and any passed in options so that you didn't need to pass all options in just to override one of them.

Created a testUtils helper utility that also merges the options and calls the evaluate method. This will also allow us to not have to pass in default check options for tests in #2216 and #2215 (simplifying those greatly). Since the evaluate methods are never called directly but instead through check.run, having a wrapper to call that does the options merging is actually more closely tied to how we call the API.

I also updated all check tests to use the new function (simple find and replace).

The important files (not find/replaced):

• all /lib files
• all test/core and test/public files
• test/testutils.js
• test/checks/aria/aria-valid-attr-evaluate.js
• test/checks/aria/aria-valid-attr-value-evaluate.js
• test/checks/language/valid-lang-evaluate.js
• test/checks/shared/non-empty-alt.js
• test/checks/shared/non-empty-value.js
• test/checks/shared/non-empty-title.js

Closes issue: #2191

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[WilcoFiers]

minor stuff

Resolved