I need to test a tantalum capacitor(check if it gets shorted for a spike higher than the rated voltage) and I'm planning for providing voltage spikes to the input connector from a bench top power supply. Is there any technique apart from switching the supply ON and OFF quickly to provide a voltage spike?
Values to get the results you want, by experimentation and observation, or by calculation if so inclined. It's foolish to knowingly exceed the ratings of a type of capacitor known for spectacular failures - you should concentrate on clamping/dumping any such pulse so that the capacitor does not see it - using any part beyond its ratings is a poor design choice and subject to any manufacturing change which meets the rated behavior but changes the beyond-rated behavior.
Depending on what you actually want/need you can add additional resistance in series with C1 or in parallel with Q1
It is typical that when you devise a particular testing scheme you have to design and configure the test setup as well. That could be the use and integration of ready made lab equipment or you could be building you your own test sets. (Note that it is not uncommon to use a combination of these approaches, for example, using a pulse generator to trigger a high voltage driver circuit that you build. Another example may be a ready made MCU board like an Arduino to activate a driver/monitor circuit).