Explain why we need to do `dapr uninstall --all` with regard to exporters component

[tcnghia]

What content needs to be created or modified? Currently upgrade instruction from 0.11 asks users to do dapr uninstall --all without explaining that we needs such instruction because of https://github.com/dapr/dapr/issues/2522 .

Describe the solution you'd like Clarify the instruction, so that users seeing the issues can be pointed to.

Where should the new material be placed?

• Observability docs
• Upgrade instructions from 0.11

Additional context cc @wcs1only

[orizohar]

@tcnghia is this still relevant post v1.0?