Avoid accessing packageCompilation() directly from project.currentPackage()

[IMS94]

Description:
Right now there are 2 locations in ls extensions where the package compilation is accessed directly.

1. BallerinaTriggerModifyUtil
2. BallerinaTreeModifyUtil
   Accessing the compilation directly may lead to concurrency issues. Therefore, the recommended approach is to use the workspaceManager.waitAndGetPackageCompilation() method.

Also the above 2 occurrences update the text document manually which is unsafe as well. We should come up with a concurrency safe approach if there's such a risk.

Describe your task(s)
We should update the above occurrences to access the packageCompilation via workspace manager