the way to do this is to separate the lights and pin them to the cloth sim.
separate each light to it's own object
at the top of every light create an empty
use Shift S to snap the 3d curser to the vertices at the top of each lamp and add an empty there
Step 3: Select 1 of the empties and Shift select after that the wire
Step 4: go into edit mode and find the nearest vertex and select only it.
Step 5: Now that our empty and our vertex are selected, press Ctrl+P and click "Make Vertex Parent"
Step 6: go out of edit mode and deselect all. Now Select the Lamp were working with and then select the corresponding empty.
Step 7: Press Ctrl+P again and parent the lamp to the empty with the "Keep Transform" option
Step 8: Repeat from Step 3 to Step 7 for each lamp and corresponding empty
Step 9: Make sure only the wire has the Cloth simulation
And Were Done!
(I know I went into detail, but since a lot of people deal with cloth simulations I want this answer to be good for beginners as well)