Review template string rules

Currently, we prefer single-quoted string literals and template strings over concatenation using `+`. We also permit backticks (i.e. "`") for strings that do not have any templates. Should we permit backticks for string literals without any templates? Is this even configurable?

No files or tests are named. Start by locating the ESLint rules that govern quote style and template strings, then determine whether backticks without interpolation are currently allowed or configurable; done requires a resolved policy and corresponding configuration or documentation.

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