This is a standard programming practice intended to reduce bugs in code. As a refresher, the final modifier prevents a primitive variable or object reference variable from being reassigned. Thus, primitives are immutable, and a reference can ever point to the object it initially pointed to. (This does not affect what methods you can call, even ones that would mutate the object's internal state.)
Every IDE I've used in the past 10 years has had the ability to inspect the code in a method and deterministically apply the final modifier to a local variable that is not reassigned after it is initialized. The idea behind this is that if you wrote code, and saved it (which runs save actions that apply the final modifier) you probably don't mean to modify that variable again. If you DO intend to modify that variable, you can simply remove the modifier. Under this logic, every variable is final until someone actively decides it should not be.
As with all things programming, there are counter arguments to this. One is it clutters the code, increasing the workload on a programmer trying to read the code to maintain it. While this hasn't been my personal experience with this modifier, I know it has been with other practices for me so I don't want to dismiss this outright simply because it doesn't apply to me. The other is that if you only use it on ones that you decide should be final (as opposed to blanketing the code with final) you're sending a message to other developers that this variable should never change - that it should stand out among other variables as one you should not attempt to change.
PDHide's comment about limiting the use of parallel execution is related - final variables are eligible to be used in lambdas and parallel processing while other variables are not. Now I believe (it's been a while) the Java compiler will allow you to use a variable that is effectively final even if it is not explicitly final but then if someone decides to modify the variable before the parallel execution, the compiler can no longer say that it's effectively final and thus no longer eligible for the parallel processing and will throw a compile error. Easily fixed, but can be annoying nevertheless.
At the end of the day, you will want to have a brief conversation with your team to decide what will work best for you. The keyword has zero impact on the actual execution or efficiency, and it's all a matter of programmer productivity.