Fix: Use correct cache directory for file logging (#1564)

## Describe your changes

## Checklist before requesting a review
- [ ] Add unit tests for this change.
- [ ] Make sure all tests can pass.
- [ ] Update documents if necessary.
- [x] Lint and apply fixes to your code by running `lintrunner -a`
- [ ] Is this a user-facing change? If yes, give a description of this
change to be included in the release notes.
- [ ] Is this PR including examples changes? If yes, please remember to
update [example
documentation](https://github.com/microsoft/Olive/blob/main/docs/source/examples.md)
in a follow-up PR.

## (Optional) Issue link

Author: tezheng

olive/engine/engine.py

@@ -94,7 +94,7 @@ def __init__(
     def initialize(self, log_to_file: bool = False, log_severity_level: int = 1):
         """Initialize engine state. This should be done before running the registered passes."""
         if log_to_file:
-            enable_filelog(log_severity_level, self.cache.cache_dir, self.workflow_id)
+            enable_filelog(log_severity_level, self.cache.dirs.cache_dir, self.workflow_id)
 
         # set cache dir environment variables
         # might be used by other parts of olive to cache data