Create common problems/solutions doc

[pwright]

removed following as it doesn't have solutions:

Resolving common problems

Use these common symptoms and messages to identify simple Skupper configuration problems.

The following issues and workarounds might help you debug simple scenarios when evaluating Skupper.

• Container platform error:

  Failed to bootstrap: failed to load site state: error loading "/home/user/.local/share/skupper/namespaces/default/input/resources/sites/test.yaml": multiple sites found, but only one site is allowed for bootstrapping
  

• namespace error:

  there is already a site created for this namespace