Bailout-shy lawmakers are continuing their search for the quietest possible way to keep the thrift cleanup and the bank deposit-insurance fund afloat through next year. The Bank Insurance Fund and the Resolution Trust Corp. need combined financing of up to $200 billion through 1992. The scenario for minimizing publicity goes like this: Money for the nearly broke BIF is included in a House banking-reform bill. When the measure gets to the Senate, the thrift funding will be tacked on. The whole issue can then be resolved in a conference committee, avoiding a messy House floor fight.