Add tests for `isStringAWayOfSayingFalse` utility

Add a file `workspaces/util/src/__tests__/isStringAWayOfSayingFalse-test.ts`, for testing the `isStringAWayOfSayingFalse` utility.

To see some PRs that add tests, take a look at #288 and #290 for inspiration.

Create workspaces/util/src/__tests__/isStringAWayOfSayingFalse-test.ts and use PRs #288 and #290 as examples of the repository's test style. Read the isStringAWayOfSayingFalse utility to identify its expected cases, then run the relevant test command and confirm the new tests pass.

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