function checkSpacingAroundFirstToken(node) {
			const firstToken = node && sourceCode.getFirstToken(node);

			if (firstToken && firstToken.type === "Keyword") {
				checkSpacingAround(firstToken);
			}
		}
Reports the first token of a given node if the first token is a keyword
and usage of spacing around the token is invalid.
@param {ASTNode|null} node A node to report.
@returns {void}