[Docs] Testing environment state mismatch

[devbugging]

It seems like the test script and the contracts and transactions executed using Test.executeTransaction are not sharing an environment. This is not clear anywhere in the documentation. Accessing block information, for example, from the scripts executed and within the test, doesn't result in the same block.

[joshuahannan]

Confirmed this myself. The timestamp returned when using getCurrentBlock().timestamp directly in the tests is different than when I query it in a script and return the value. Additionally, the timestamp (queried from scripts) seems to increase on its own as I run transactions, whereas I thought that the timestamp should only increase if I use the Test.moveTime utility.

Also, the values when querying contract fields are sometimes different when querying directly vs querying with a script

[joshuahannan]

@m-Peter I think this and #446 are basically describing the same thing. Feel free to close one of them if you want to consolidate

[m-Peter]

@joshuahannan I think the state mismatch between the testing environment and the blockchain is basically the difference between the two types of testing strategies allowed by the Cadence testing framework, unit tests & integration tests. I've added here: https://github.com/onflow/flow-core-contracts/pull/518/files#r2318545065 a more elaborate answer.