updated readme

Author: andy-wm-arthur

bats/compatibility/README.md

@@ -18,6 +18,6 @@ and the repositories created with those versions.
 The BATS tests used to verify compatibility are inherently fragile.
 Our primary integration tests in `/dolt/bats/` setup and tear down their environment for each test.
 Because the tests rely on creating a repo with one version of Dolt and running BATS tests with a different version, 
-we cannot isolate their environment without building Dolt twice per test.
+we cannot isolate their environment without building Dolt twice per test or setting up a different Dolt repo per test.
 The initial version of these tests does all write operations in the `setup_repo.sh` script, and limits state modifications
 within the BATS test to `dolt checkout` branch changes. Take care when editing the BATS tests to follow this pattern.