WASHINGTON — The IRS suspended a $7.25 million contract with the credit reporting company Equifax on Friday after members of Congress complained the tax agency had awarded a no-bid contract to a company that recently had a massive data breach. The IRS had contracted with Equifax to validate the identity of taxpayers communicating with the agency on the telephone or through its website. In a statement Friday, the IRS said it suspended the contract as “a precautionary step” while the agency reviews the company’s security systems. “During this suspension, the IRS will continue its review of Equifax systems and security,” the statement said.