Upgrade to oik-bwtrace v3.4.3 to fix a problem introduced in v3.4.2. When the mu-plugins folder is not present warning messages are produced attempting to write trace’s `.json` files, used when performance tracing.

Changes
| Change | Reference |
|---|---|
| Fixed: Caters for mu-plugins folder not being present | bobbingwide/oik-bwtrace#109 |
Tested
- Tested: With WordPress 6.3.1 and WordPress Multisite
- Tested: With WordPress 6.4-beta3 and WordPress Multisite
- Tested: With PHPUnit 9.6
- Tested: With PHP 8.0, 8.1 and 8.2
