Workflow: delete and recreate directory for codecoverage

[BrianHenryIE]

Proposed changes

There was a problem with the workflow where it tried to set the current working directory to one that didn't yet exist

Run rm -rf *

Error: An error occurred trying to start process '/usr/bin/bash' with working directory '/home/runner/work/wp-module-data/wp-module-data/gh-pages/phpunit'. No such file or directory

This fix deletes and recreates the directory from the project root instead.

Type of Change

• Bugfix (non-breaking change which fixes an issue)

Checklist

Further comments