Consistent use of ENABLE in boolean environment variables

Now that we have have achieved consistency by using PMM_ prefix in PMM env variables ( ) and removed dual booleans from our API ( ) we also want to use the word “ENABLE“ for the boolean variable.

Currently, we use both “ENABLE” and “DISABLE” in boolean env variable naming, which makes it challenging to remember which is should be used without consulting PMM documentation.

Therefore, we want to rename all mentions of “DISABLE” to “ENABLE” and reverse the logic as appropriate.