NEW DELHI — India’s central bank has cut its key interest rate for the fourth consecutive time, reducing the repo rate by 0.35% to 5.40% to shore up the economy, with consumer spending and corporate investment faltering and the production of capital goods and consumer durables decelerating.In a bimonthly review of the economy Wednesday, the bank trimmed the GDP growth forecast for the current fiscal year to 6.9% from 7%.The benchmark interest rate is what the Reserve Bank of India charges on lending to commercial banks.The bank maintained an accommodative stance for monetary policy, implying that an increase in interest rates is off the table.Lower interest rates help make credit cheaper for borrowers, though they can also spur inflation.The Associated Press