[BUGFIX] Isolated behat steps should clear configuration caches
The change I65211ddd90484ec1a9d970394f0b9d268805ea9f uncovered an
issue with isolated behat steps as they relied on the wrong behavior
that configuration caches would be cleared on every development
request. This change adds clearing of Configuration caches to the
other cache clearings happening for each isolated step.
Releases: master, 3.0