These may just be coincidences and be tiny shards of normal flooded caves, but they also may possibly be springs which have no connection to an adjacent air block but generated anyway. If the latter, this is a bug.
Seed: 1
Coordinates: /execute in minecraft:overworld run tp @s 502.50 -23.62 -303.50 -22.45 30.70
Can confirm. Just to make life easier, here is the seed along with the coordinates so you can just copy + paste this info and reproduce the issue.