* List inbuilt sources if CRD access is restricted
Fixes#947
- Identify restricted access error
- If server returns restricted access error, fallback to listing
only eventing inbuilt sources using their GVKs.
- List any inbuilt source (ApiServerSource) object and read the error
to know if eventing is installed for `kn source list-types`.
* Fix golint warnings
* Remove unused imports
* Verify each built in source before listing source types
* Improve the check if sources are not installed in the cluster
* Update finding forbidden error
* Update finding errors
* Add unit tests for IsForbiddenError util
* Add unit tests
* Add tests for dynamic pkg library
* Add unit tests for case when no sources are installed
* Update test name
* chore: Update to Knative serving/eventing 0.14.0
and also move ApiServerSource to v1alpha2, adapting the option
(from "controller" to "labelSelector")
* fix go.sum
* chore: Update and fix tests
* chore: fix go.sum
* chore(e2e): Optimized tests
Smoke Tests now run before the E2E tests, but in the same cluster
* chore: Removed unneeded test
* fix
* fix
* fix
* fix
* chore: Update to serving & eventing v0.13.0
* refactor(source): Update to Knative eventing 0.13.0
* Moved to "sources.knative.dev" API group
* Replaced CronJobSource with PingSource (and removed unsupported options for service account, requests limits)
* Move to versions:
- SinkBinding v1alpha2
- PingSource v1alpha2
- ApiServerSource v1alpha1
* update to eventing 0.13.1
* go.sum fix
* fixed test
* test updates
* try to enhance error output
* fix test.
* update tests infra to 0.13.1
Ying Chun Guo