'execute if/unless score' sets the score to 0 if unset

The bug

Using /execute if/unless score and testing for players which do not have a score sets 0 for them and the test succeeds.

Expected would be that the comparison failed and no score was set.

How to reproduce

1. Create a new objective called something like test
2. Run the following to set the value to test with

   /scoreboard players set value test 0
   

3. Run

   /execute if score something test = value test run say test
   

   The command runs successfully even though the player "something" hasn't been initialized in the objective "test"