isStringLiteral(node) {
		return (
			(node.type === "Literal" && typeof node.value === "string") ||
			node.type === "TemplateLiteral"
		);
	}
Checks whether or not a given node is a string literal.
@param {ASTNode} node A node to check.
@returns {boolean} `true` if the node is a string literal.