Avoid displaying syntax error as log message (#11902)
## Summary
Follow-up to #11901
This PR avoids displaying the syntax errors as log message now that the
`E999` diagnostic cannot be disabled.
For context on why this was added, refer to
https://github.com/astral-sh/ruff/pull/2505. Basically, we would allow
ignoring the syntax error diagnostic because certain syntax feature
weren't supported back then like `match` statement. And, if a user
ignored `E999`, Ruff would give no feedback if the source code contained
any syntax error. So, this log message was a way to indicate to the user
even if `E999` was disabled.
The current state of the parser is such that (a) it matches with the
latest grammar and (b) it's easy to add support for any new syntax.
**Note:** This PR doesn't remove the `DisplayParseError` struct because
it's still being used by the formatter.
## Test Plan
Update existing snapshots from the integration tests.
