Improve migration script from unomi 1.x to 2.x to take target.properties.path into account

In the code sample of the Unomi tracker 1.x, the path of the page was passed in the unomi event as: target.properties.path.

https://github.com/apache/unomi/blob/2ea65451dfb9e7cdcc6fdb87e2ec57d98d68d9dc/extensions/web-tracker/wab/src/main/webapp/index.html#L49

It's likely that developers used that sample.

=> Since there are events validation in Unomi 2, the migration scripts should be updated to take this feld into account and move it to target.properties.pageInfo.pagePath, only for page view events