RIO DE JANEIRO, June 30 (Reuters) - Brazilian President Jair Bolsonaro, under pressure over allegations of corruption in his government"s vaccine procurement drive, said on Wednesday he would not be taken down by a high-profile Senate inquiry. Senators are probing his government"s handling of the coronavirus pandemic in Brazil, home to the world"s second deadliest outbreak, and have uncovered allegations of backroom deals between officials and private sector intermediaries that have heaped pressure on Bolsonaro ahead of next year"s election.