You can remove the lamps that are not working. This will only let the one good light to work. Perhaps one light was faulty already before you moved in and the other was ready to go bad. It will use less power and will be of no concern, I believe you operate it with only one lamp.
So you will have an idea what the condition of the lamps are, and using the picture you offered, these type of lamps when they are going bad or have gone bad, get dark spots on the ends close to where they connect to the fixture. The darkening occurs in the glass, not the porcelain. Take for example the last lamp on the right, where it connects has some darkening at the base, where the other 2 lamps do not. The lamp on the right will not work anymore in time, or perhaps is already not lighting up (glowing). These words are interchangeable here. If your lamps in the fixture of your room have dark spots at the base, close to the end or ends that plug into the fixture, then it is most likely that the lamps are bad. It does not hurt to leave them in that I know of, they may still draw some power.
If you prefer not to have the room heavily lit, you will do fine by removing them temporarily and replace them in 9 months before you leave the rental, or replace them with new lamps if you wish, as a good gesture towards your landlord.
Your design is dangerous because you don't have safe light fixtures. Outdoor light fixtures, especially at 220V, need to safely insulate all electrical conductors. In an environment full of moisture and active, moving animals, you need fixtures that are secure and sealed. If you can't buy these, maybe you can make some, but don't expect regular indoor fixtures to be safe.
Let's think about how this system gets dangerous. Some of the wiring gets exposed, and a person or animal gets between the hot and neutral legs, completing the circuit. This could happen with two adjacent puddles of water, maybe one touching a hot and the other a neutral. Or a puddle and a rake that's pierced some of your above-ground cabling.
Your "ground" wire doesn't help. Bonding neutral to ground is good because it means that a loose hot wire that touches some exposed metal (or other good conductor bonded to ground) will blow the fuse quickly. You're not in an environment with lots of good conductors; even wet dirt may not conduct well enough to blow the fuse. If you had for example a metal walkway and a nearby metal pipe, you should definitely bond those so they can't be separately energized. But if you're just talking about an electrical system out in a field, bonding the field to neutral doesn't buy you much.
An RCD (residual current device) or GFI (ground fault interruptor) may not help much either, because again you're not likely to leak current to ground. However, these might be a little more sensitive than your fuse so they could help a bit.
The safe approach here is to use proper light fixtures designed for outdoor use in wet areas. These can be low-voltage or high. Low voltage is safer, because even if the fixtures or wiring fails the available energy is not enough to kill you. But a 220V setup that includes sufficient protection for your junctions and the light bulbs would also be relatively safe.
If you stick with your design, at least realize that your ground does not make it any safer. Protect your fixtures and junctions from moisture and from access by people and livestock.
Best Answer
Normally the contractor removes the fixtures and outlets. In most states you do not have to be a licensed electrician to remove replace existing fixtures and outlets, (I believe there are a couple that may require it from reading different forums). You do want the siding company to mount the fixtures or they may end up looking bad. The siding company has the trim and experiance where an electrician may have no experiance with the siding type.